diff --git a/homeassistant/components/device_tracker/__init__.py b/homeassistant/components/device_tracker/__init__.py
index b646f93e2d0c..6ad4755b0b52 100644
--- a/homeassistant/components/device_tracker/__init__.py
+++ b/homeassistant/components/device_tracker/__init__.py
@@ -1,6 +1,4 @@
 """
-homeassistant.components.device_tracker
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 Provides functionality to keep track of devices.
 
 For more details about this component, please refer to the documentation at
@@ -70,7 +68,7 @@ _LOGGER = logging.getLogger(__name__)
 
 
 def is_on(hass, entity_id=None):
-    """ Returns if any or specified device is home. """
+    """Returns if any or specified device is home."""
     entity = entity_id or ENTITY_ID_ALL_DEVICES
 
     return hass.states.is_state(entity, STATE_HOME)
@@ -78,7 +76,7 @@ def is_on(hass, entity_id=None):
 
 def see(hass, mac=None, dev_id=None, host_name=None, location_name=None,
         gps=None, gps_accuracy=None, battery=None):
-    """ Call service to notify you see device. """
+    """Call service to notify you see device."""
     data = {key: value for key, value in
             ((ATTR_MAC, mac),
              (ATTR_DEV_ID, dev_id),
@@ -89,7 +87,7 @@ def see(hass, mac=None, dev_id=None, host_name=None, location_name=None,
 
 
 def setup(hass, config):
-    """ Setup device tracker """
+    """Setup device tracker."""
     yaml_path = hass.config.path(YAML_DEVICES)
 
     conf = config.get(DOMAIN, {})
@@ -108,7 +106,7 @@ def setup(hass, config):
                             devices)
 
     def setup_platform(p_type, p_config, disc_info=None):
-        """ Setup a device tracker platform. """
+        """Setup a device tracker platform."""
         platform = prepare_setup_platform(hass, config, DOMAIN, p_type)
         if platform is None:
             return
@@ -134,7 +132,7 @@ def setup(hass, config):
         setup_platform(p_type, p_config)
 
     def device_tracker_discovered(service, info):
-        """ Called when a device tracker platform is discovered. """
+        """Called when a device tracker platform is discovered."""
         setup_platform(DISCOVERY_PLATFORMS[service], {}, info)
 
     discovery.listen(hass, DISCOVERY_PLATFORMS.keys(),
@@ -148,7 +146,7 @@ def setup(hass, config):
     tracker.setup_group()
 
     def see_service(call):
-        """ Service to see a device. """
+        """Service to see a device."""
         args = {key: value for key, value in call.data.items() if key in
                 (ATTR_MAC, ATTR_DEV_ID, ATTR_HOST_NAME, ATTR_LOCATION_NAME,
                  ATTR_GPS, ATTR_GPS_ACCURACY, ATTR_BATTERY)}
@@ -163,7 +161,7 @@ def setup(hass, config):
 
 
 class DeviceTracker(object):
-    """ Track devices """
+    """Represents a device tracker."""
     def __init__(self, hass, consider_home, track_new, home_range, devices):
         self.hass = hass
         self.devices = {dev.dev_id: dev for dev in devices}
@@ -181,7 +179,7 @@ class DeviceTracker(object):
 
     def see(self, mac=None, dev_id=None, host_name=None, location_name=None,
             gps=None, gps_accuracy=None, battery=None):
-        """ Notify device tracker that you see a device. """
+        """Notify device tracker that you see a device."""
         with self.lock:
             if mac is None and dev_id is None:
                 raise HomeAssistantError('Neither mac or device id passed in')
@@ -220,14 +218,14 @@ class DeviceTracker(object):
             update_config(self.hass.config.path(YAML_DEVICES), dev_id, device)
 
     def setup_group(self):
-        """ Initializes group for all tracked devices. """
+        """Initializes group for all tracked devices."""
         entity_ids = (dev.entity_id for dev in self.devices.values()
                       if dev.track)
         self.group = group.Group(
             self.hass, GROUP_NAME_ALL_DEVICES, entity_ids, False)
 
     def update_stale(self, now):
-        """ Update stale devices. """
+        """Update stale devices."""
         with self.lock:
             for device in self.devices.values():
                 if (device.track and device.last_update_home and
@@ -236,8 +234,7 @@ class DeviceTracker(object):
 
 
 class Device(Entity):
-    """ Tracked device. """
-
+    """Represents a tracked device."""
     host_name = None
     location_name = None
     gps = None
@@ -245,7 +242,7 @@ class Device(Entity):
     last_seen = None
     battery = None
 
-    # Track if the last update of this device was HOME
+    # Track if the last update of this device was HOME.
     last_update_home = False
     _state = STATE_NOT_HOME
 
@@ -276,29 +273,29 @@ class Device(Entity):
 
     @property
     def gps_home(self):
-        """ Return if device is within range of home. """
+        """Return if device is within range of home."""
         distance = max(
             0, self.hass.config.distance(*self.gps) - self.gps_accuracy)
         return self.gps is not None and distance <= self.home_range
 
     @property
     def name(self):
-        """ Returns the name of the entity. """
+        """Returns the name of the entity."""
         return self.config_name or self.host_name or DEVICE_DEFAULT_NAME
 
     @property
     def state(self):
-        """ State of the device. """
+        """Return the state of the device."""
         return self._state
 
     @property
     def entity_picture(self):
-        """Picture of the device."""
+        """Return the picture of the device."""
         return self.config_picture
 
     @property
     def state_attributes(self):
-        """ Device state attributes. """
+        """Return the device state attributes."""
         attr = {}
 
         if self.gps:
@@ -313,12 +310,12 @@ class Device(Entity):
 
     @property
     def hidden(self):
-        """ If device should be hidden. """
+        """If device should be hidden."""
         return self.away_hide and self.state != STATE_HOME
 
     def seen(self, host_name=None, location_name=None, gps=None,
              gps_accuracy=0, battery=None):
-        """ Mark the device as seen. """
+        """Mark the device as seen."""
         self.last_seen = dt_util.utcnow()
         self.host_name = host_name
         self.location_name = location_name
@@ -336,12 +333,12 @@ class Device(Entity):
         self.update()
 
     def stale(self, now=None):
-        """ Return if device state is stale. """
+        """Return if device state is stale."""
         return self.last_seen and \
             (now or dt_util.utcnow()) - self.last_seen > self.consider_home
 
     def update(self):
-        """ Update state of entity. """
+        """Update state of entity."""
         if not self.last_seen:
             return
         elif self.location_name:
@@ -365,7 +362,7 @@ class Device(Entity):
 
 
 def load_config(path, hass, consider_home, home_range):
-    """ Load devices from YAML config file. """
+    """Load devices from YAML configuration file."""
     if not os.path.isfile(path):
         return []
     return [
@@ -377,7 +374,7 @@ def load_config(path, hass, consider_home, home_range):
 
 
 def setup_scanner_platform(hass, config, scanner, see_device):
-    """ Helper method to connect scanner-based platform to device tracker. """
+    """Helper method to connect scanner-based platform to device tracker."""
     interval = util.convert(config.get(CONF_SCAN_INTERVAL), int,
                             DEFAULT_SCAN_INTERVAL)
 
@@ -385,7 +382,7 @@ def setup_scanner_platform(hass, config, scanner, see_device):
     seen = set()
 
     def device_tracker_scan(now):
-        """ Called when interval matches. """
+        """Called when interval matches."""
         for mac in scanner.scan_devices():
             if mac in seen:
                 host_name = None
@@ -401,7 +398,7 @@ def setup_scanner_platform(hass, config, scanner, see_device):
 
 
 def update_config(path, dev_id, device):
-    """ Add device to YAML config file. """
+    """Add device to YAML configuration file."""
     with open(path, 'a') as out:
         out.write('\n')
         out.write('{}:\n'.format(device.dev_id))
diff --git a/homeassistant/components/device_tracker/actiontec.py b/homeassistant/components/device_tracker/actiontec.py
index d9cb8718a70f..8e9bf59c7752 100644
--- a/homeassistant/components/device_tracker/actiontec.py
+++ b/homeassistant/components/device_tracker/actiontec.py
@@ -1,8 +1,5 @@
 """
-homeassistant.components.device_tracker.actiontec
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Device tracker platform that supports scanning an Actiontec MI424WR
-(Verizon FIOS) router for device presence.
+Support for Actiontec MI424WR (Verizon FIOS) routers.
 
 For more details about this platform, please refer to the documentation at
 https://home-assistant.io/components/device_tracker.actiontec/
@@ -20,7 +17,7 @@ from homeassistant.const import CONF_HOST, CONF_PASSWORD, CONF_USERNAME
 from homeassistant.helpers import validate_config
 from homeassistant.util import Throttle
 
-# Return cached results if last scan was less then this time ago
+# Return cached results if last scan was less then this time ago.
 MIN_TIME_BETWEEN_SCANS = timedelta(seconds=5)
 
 _LOGGER = logging.getLogger(__name__)
@@ -34,7 +31,7 @@ _LEASES_REGEX = re.compile(
 
 # pylint: disable=unused-argument
 def get_scanner(hass, config):
-    """ Validates config and returns an Actiontec scanner. """
+    """Validates configuration and returns an Actiontec scanner."""
     if not validate_config(config,
                            {DOMAIN: [CONF_HOST, CONF_USERNAME, CONF_PASSWORD]},
                            _LOGGER):
@@ -50,7 +47,6 @@ class ActiontecDeviceScanner(object):
     This class queries a an actiontec router for connected devices.
     Adapted from DD-WRT scanner.
     """
-
     def __init__(self, config):
         self.host = config[CONF_HOST]
         self.username = config[CONF_USERNAME]
@@ -65,12 +61,11 @@ class ActiontecDeviceScanner(object):
         """
         Scans for new devices and return a list containing found device ids.
         """
-
         self._update_info()
         return [client.mac for client in self.last_results]
 
     def get_device_name(self, device):
-        """ Returns the name of the given device or None if we don't know. """
+        """Returns the name of the given device or None if we don't know."""
         if not self.last_results:
             return None
         for client in self.last_results:
@@ -100,7 +95,7 @@ class ActiontecDeviceScanner(object):
             return True
 
     def get_actiontec_data(self):
-        """ Retrieve data from Actiontec MI424WR and return parsed result. """
+        """Retrieve data from Actiontec MI424WR and return parsed result."""
         try:
             telnet = telnetlib.Telnet(self.host)
             telnet.read_until(b'Username: ')
diff --git a/homeassistant/components/device_tracker/aruba.py b/homeassistant/components/device_tracker/aruba.py
index 4bc3f9e32585..fb5e8c1ef592 100644
--- a/homeassistant/components/device_tracker/aruba.py
+++ b/homeassistant/components/device_tracker/aruba.py
@@ -1,8 +1,5 @@
 """
-homeassistant.components.device_tracker.aruba
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Device tracker platform that supports scanning a Aruba Access Point for device
-presence.
+Support for Aruba Access Points.
 
 For more details about this platform, please refer to the documentation at
 https://home-assistant.io/components/device_tracker.aruba/
@@ -31,7 +28,7 @@ _DEVICES_REGEX = re.compile(
 
 # pylint: disable=unused-argument
 def get_scanner(hass, config):
-    """ Validates config and returns a Aruba scanner. """
+    """Validates configuration and returns a Aruba scanner."""
     if not validate_config(config,
                            {DOMAIN: [CONF_HOST, CONF_USERNAME, CONF_PASSWORD]},
                            _LOGGER):
@@ -43,8 +40,7 @@ def get_scanner(hass, config):
 
 
 class ArubaDeviceScanner(object):
-    """ This class queries a Aruba Acces Point for connected devices. """
-
+    """This class queries a Aruba Access Point for connected devices."""
     def __init__(self, config):
         self.host = config[CONF_HOST]
         self.username = config[CONF_USERNAME]
@@ -62,12 +58,11 @@ class ArubaDeviceScanner(object):
         """
         Scans for new devices and return a list containing found device IDs.
         """
-
         self._update_info()
         return [client['mac'] for client in self.last_results]
 
     def get_device_name(self, device):
-        """ Returns the name of the given device or None if we don't know. """
+        """Returns the name of the given device or None if we don't know."""
         if not self.last_results:
             return None
         for client in self.last_results:
@@ -93,8 +88,7 @@ class ArubaDeviceScanner(object):
             return True
 
     def get_aruba_data(self):
-        """ Retrieve data from Aruba Access Point and return parsed result. """
-
+        """Retrieve data from Aruba Access Point and return parsed result."""
         import pexpect
         connect = "ssh {}@{}"
         ssh = pexpect.spawn(connect.format(self.username, self.host))
diff --git a/homeassistant/components/device_tracker/asuswrt.py b/homeassistant/components/device_tracker/asuswrt.py
index d9b6d1a809e1..5d3b01b55945 100644
--- a/homeassistant/components/device_tracker/asuswrt.py
+++ b/homeassistant/components/device_tracker/asuswrt.py
@@ -1,8 +1,5 @@
 """
-homeassistant.components.device_tracker.asuswrt
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Device tracker platform that supports scanning a ASUSWRT router for device
-presence.
+Support for ASUSWRT routers.
 
 For more details about this platform, please refer to the documentation at
 https://home-assistant.io/components/device_tracker.asuswrt/
@@ -18,7 +15,7 @@ from homeassistant.const import CONF_HOST, CONF_PASSWORD, CONF_USERNAME
 from homeassistant.helpers import validate_config
 from homeassistant.util import Throttle
 
-# Return cached results if last scan was less then this time ago
+# Return cached results if last scan was less then this time ago.
 MIN_TIME_BETWEEN_SCANS = timedelta(seconds=5)
 
 _LOGGER = logging.getLogger(__name__)
@@ -39,7 +36,7 @@ _IP_NEIGH_REGEX = re.compile(
 
 # pylint: disable=unused-argument
 def get_scanner(hass, config):
-    """ Validates config and returns an ASUS-WRT scanner. """
+    """Validates configuration and returns an ASUS-WRT scanner."""
     if not validate_config(config,
                            {DOMAIN: [CONF_HOST, CONF_USERNAME, CONF_PASSWORD]},
                            _LOGGER):
@@ -55,7 +52,6 @@ class AsusWrtDeviceScanner(object):
     This class queries a router running ASUSWRT firmware
     for connected devices. Adapted from DD-WRT scanner.
     """
-
     def __init__(self, config):
         self.host = config[CONF_HOST]
         self.username = str(config[CONF_USERNAME])
@@ -73,12 +69,11 @@ class AsusWrtDeviceScanner(object):
         """
         Scans for new devices and return a list containing found device IDs.
         """
-
         self._update_info()
         return [client['mac'] for client in self.last_results]
 
     def get_device_name(self, device):
-        """ Returns the name of the given device or None if we don't know. """
+        """Returns the name of the given device or None if we don't know."""
         if not self.last_results:
             return None
         for client in self.last_results:
@@ -109,7 +104,7 @@ class AsusWrtDeviceScanner(object):
             return True
 
     def get_asuswrt_data(self):
-        """ Retrieve data from ASUSWRT and return parsed result. """
+        """Retrieve data from ASUSWRT and return parsed result."""
         try:
             telnet = telnetlib.Telnet(self.host)
             telnet.read_until(b'login: ')
@@ -138,9 +133,8 @@ class AsusWrtDeviceScanner(object):
                 _LOGGER.warning("Could not parse lease row: %s", lease)
                 continue
 
-            # For leases where the client doesn't set a hostname, ensure
-            # it is blank and not '*', which breaks the entity_id down
-            # the line
+            # For leases where the client doesn't set a hostname, ensure it is
+            # blank and not '*', which breaks the entity_id down the line.
             host = match.group('host')
             if host == '*':
                 host = ''
diff --git a/homeassistant/components/device_tracker/ddwrt.py b/homeassistant/components/device_tracker/ddwrt.py
index 82a8ed81537d..70c97a1226f0 100644
--- a/homeassistant/components/device_tracker/ddwrt.py
+++ b/homeassistant/components/device_tracker/ddwrt.py
@@ -1,8 +1,5 @@
 """
-homeassistant.components.device_tracker.ddwrt
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Device tracker platform that supports scanning a DD-WRT router for device
-presence.
+Support for DD-WRT routers.
 
 For more details about this platform, please refer to the documentation at
 https://home-assistant.io/components/device_tracker.ddwrt/
@@ -19,7 +16,7 @@ from homeassistant.const import CONF_HOST, CONF_PASSWORD, CONF_USERNAME
 from homeassistant.helpers import validate_config
 from homeassistant.util import Throttle
 
-# Return cached results if last scan was less then this time ago
+# Return cached results if last scan was less then this time ago.
 MIN_TIME_BETWEEN_SCANS = timedelta(seconds=5)
 
 _LOGGER = logging.getLogger(__name__)
@@ -30,7 +27,7 @@ _MAC_REGEX = re.compile(r'(([0-9A-Fa-f]{1,2}\:){5}[0-9A-Fa-f]{1,2})')
 
 # pylint: disable=unused-argument
 def get_scanner(hass, config):
-    """ Validates config and returns a DD-WRT scanner. """
+    """Validates config and returns a DD-WRT scanner."""
     if not validate_config(config,
                            {DOMAIN: [CONF_HOST, CONF_USERNAME, CONF_PASSWORD]},
                            _LOGGER):
@@ -47,7 +44,6 @@ class DdWrtDeviceScanner(object):
     This class queries a wireless router running DD-WRT firmware
     for connected devices. Adapted from Tomato scanner.
     """
-
     def __init__(self, config):
         self.host = config[CONF_HOST]
         self.username = config[CONF_USERNAME]
@@ -68,16 +64,14 @@ class DdWrtDeviceScanner(object):
         """
         Scans for new devices and return a list containing found device ids.
         """
-
         self._update_info()
 
         return self.last_results
 
     def get_device_name(self, device):
-        """ Returns the name of the given device or None if we don't know. """
-
+        """Returns the name of the given device or None if we don't know."""
         with self.lock:
-            # if not initialised and not already scanned and not found
+            # If not initialised and not already scanned and not found.
             if device not in self.mac2name:
                 url = 'http://{}/Status_Lan.live.asp'.format(self.host)
                 data = self.get_ddwrt_data(url)
@@ -90,15 +84,15 @@ class DdWrtDeviceScanner(object):
                 if not dhcp_leases:
                     return None
 
-                # remove leading and trailing single quotes
+                # Remove leading and trailing single quotes.
                 cleaned_str = dhcp_leases.strip().strip('"')
                 elements = cleaned_str.split('","')
                 num_clients = int(len(elements)/5)
                 self.mac2name = {}
                 for idx in range(0, num_clients):
-                    # this is stupid but the data is a single array
+                    # This is stupid but the data is a single array
                     # every 5 elements represents one hosts, the MAC
-                    # is the third element and the name is the first
+                    # is the third element and the name is the first.
                     mac_index = (idx * 5) + 2
                     if mac_index < len(elements):
                         mac = elements[mac_index]
@@ -135,7 +129,7 @@ class DdWrtDeviceScanner(object):
             # regex's out values so I guess I have to do the same,
             # LAME!!!
 
-            # remove leading and trailing single quotes
+            # Remove leading and trailing single quotes.
             clean_str = active_clients.strip().strip("'")
             elements = clean_str.split("','")
 
@@ -145,7 +139,7 @@ class DdWrtDeviceScanner(object):
             return True
 
     def get_ddwrt_data(self, url):
-        """ Retrieve data from DD-WRT and return parsed result. """
+        """Retrieve data from DD-WRT and return parsed result."""
         try:
             response = requests.get(
                 url,
@@ -167,7 +161,7 @@ class DdWrtDeviceScanner(object):
 
 
 def _parse_ddwrt_response(data_str):
-    """ Parse the DD-WRT data format. """
+    """Parse the DD-WRT data format."""
     return {
         key: val for key, val in _DDWRT_DATA_REGEX
         .findall(data_str)}
diff --git a/homeassistant/components/device_tracker/demo.py b/homeassistant/components/device_tracker/demo.py
index 43b7915ee3c5..ee0195f43cc3 100644
--- a/homeassistant/components/device_tracker/demo.py
+++ b/homeassistant/components/device_tracker/demo.py
@@ -1,10 +1,5 @@
 """
-homeassistant.components.device_tracker.demo
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 Demo platform for the device tracker.
-
-device_tracker:
-  platform: demo
 """
 import random
 
@@ -12,14 +7,13 @@ from homeassistant.components.device_tracker import DOMAIN
 
 
 def setup_scanner(hass, config, see):
-    """ Set up a demo tracker. """
-
+    """Setup the demo tracker."""
     def offset():
-        """ Return random offset. """
+        """Return random offset."""
         return (random.randrange(500, 2000)) / 2e5 * random.choice((-1, 1))
 
     def random_see(dev_id, name):
-        """ Randomize a sighting. """
+        """Randomize a sighting."""
         see(
             dev_id=dev_id,
             host_name=name,
@@ -30,7 +24,7 @@ def setup_scanner(hass, config, see):
         )
 
     def observe(call=None):
-        """ Observe three entities. """
+        """Observe three entities."""
         random_see('demo_paulus', 'Paulus')
         random_see('demo_anne_therese', 'Anne Therese')
 
diff --git a/homeassistant/components/device_tracker/fritz.py b/homeassistant/components/device_tracker/fritz.py
index 3ca3461f5578..e0bc980d3165 100644
--- a/homeassistant/components/device_tracker/fritz.py
+++ b/homeassistant/components/device_tracker/fritz.py
@@ -1,8 +1,5 @@
 """
-homeassistant.components.device_tracker.fritz
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Device tracker platform that supports scanning a FRITZ!Box router for device
-presence.
+Support for FRITZ!Box routers.
 
 For more details about this platform, please refer to the documentation at
 https://home-assistant.io/components/device_tracker.fritz/
@@ -17,15 +14,14 @@ from homeassistant.util import Throttle
 
 REQUIREMENTS = ['fritzconnection==0.4.6']
 
-# Return cached results if last scan was less then this time ago
+# Return cached results if last scan was less then this time ago.
 MIN_TIME_BETWEEN_SCANS = timedelta(seconds=5)
 
 _LOGGER = logging.getLogger(__name__)
 
 
-# noinspection PyUnusedLocal
 def get_scanner(hass, config):
-    """ Validates config and returns FritzBoxScanner. """
+    """Validates configuration and returns FritzBoxScanner."""
     if not validate_config(config,
                            {DOMAIN: []},
                            _LOGGER):
@@ -52,7 +48,7 @@ class FritzBoxScanner(object):
     """
     def __init__(self, config):
         self.last_results = []
-        self.host = '169.254.1.1'  # This IP is valid for all fritzboxes
+        self.host = '169.254.1.1'  # This IP is valid for all FRITZ!Box router.
         self.username = 'admin'
         self.password = ''
         self.success_init = True
@@ -68,7 +64,7 @@ class FritzBoxScanner(object):
         if CONF_PASSWORD in config.keys():
             self.password = config[CONF_PASSWORD]
 
-        # Establish a connection to the FRITZ!Box
+        # Establish a connection to the FRITZ!Box.
         try:
             self.fritz_box = fc.FritzHosts(address=self.host,
                                            user=self.username,
@@ -77,7 +73,7 @@ class FritzBoxScanner(object):
             self.fritz_box = None
 
         # At this point it is difficult to tell if a connection is established.
-        # So just check for null objects ...
+        # So just check for null objects.
         if self.fritz_box is None or not self.fritz_box.modelname:
             self.success_init = False
 
@@ -90,7 +86,7 @@ class FritzBoxScanner(object):
                           "with IP: %s", self.host)
 
     def scan_devices(self):
-        """ Scan for new devices and return a list of found device ids. """
+        """Scan for new devices and return a list of found device ids."""
         self._update_info()
         active_hosts = []
         for known_host in self.last_results:
@@ -99,7 +95,7 @@ class FritzBoxScanner(object):
         return active_hosts
 
     def get_device_name(self, mac):
-        """ Returns the name of the given device or None if is not known. """
+        """Returns the name of the given device or None if is not known."""
         ret = self.fritz_box.get_specific_host_entry(mac)["NewHostName"]
         if ret == {}:
             return None
@@ -107,7 +103,7 @@ class FritzBoxScanner(object):
 
     @Throttle(MIN_TIME_BETWEEN_SCANS)
     def _update_info(self):
-        """ Retrieves latest information from the FRITZ!Box. """
+        """Retrieves latest information from the FRITZ!Box."""
         if not self.success_init:
             return False
 
diff --git a/homeassistant/components/device_tracker/icloud.py b/homeassistant/components/device_tracker/icloud.py
index 4b13098dde02..3a6d1d7d9e66 100644
--- a/homeassistant/components/device_tracker/icloud.py
+++ b/homeassistant/components/device_tracker/icloud.py
@@ -1,7 +1,5 @@
 """
-homeassistant.components.device_tracker.icloud
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Device tracker platform that supports scanning iCloud devices.
+Support for iCloud connected devices.
 
 For more details about this platform, please refer to the documentation at
 https://home-assistant.io/components/device_tracker.icloud/
@@ -21,12 +19,12 @@ DEFAULT_INTERVAL = 8
 
 
 def setup_scanner(hass, config, see):
-    """ Set up the iCloud Scanner. """
+    """Setup the iCloud Scanner."""
     from pyicloud import PyiCloudService
     from pyicloud.exceptions import PyiCloudFailedLoginException
     from pyicloud.exceptions import PyiCloudNoDevicesException
 
-    # Get the username and password from the configuration
+    # Get the username and password from the configuration.
     username = config.get(CONF_USERNAME)
     password = config.get(CONF_PASSWORD)
 
@@ -45,14 +43,14 @@ def setup_scanner(hass, config, see):
         return False
 
     def keep_alive(now):
-        """ Keeps authenticating iCloud connection. """
+        """Keeps authenticating iCloud connection."""
         api.authenticate()
         _LOGGER.info("Authenticate against iCloud")
 
     track_utc_time_change(hass, keep_alive, second=0)
 
     def update_icloud(now):
-        """ Authenticate against iCloud and scan for devices. """
+        """Authenticate against iCloud and scan for devices."""
         try:
             # The session timeouts if we are not using it so we
             # have to re-authenticate. This will send an email.
diff --git a/homeassistant/components/device_tracker/locative.py b/homeassistant/components/device_tracker/locative.py
index d1912b06b3d3..0bb5b5ed3188 100644
--- a/homeassistant/components/device_tracker/locative.py
+++ b/homeassistant/components/device_tracker/locative.py
@@ -1,7 +1,5 @@
 """
-homeassistant.components.device_tracker.locative
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Locative platform for the device tracker.
+Support for the Locative platform.
 
 For more details about this platform, please refer to the documentation at
 https://home-assistant.io/components/device_tracker.locative/
@@ -20,12 +18,10 @@ URL_API_LOCATIVE_ENDPOINT = "/api/locative"
 
 
 def setup_scanner(hass, config, see):
-    """ Set up an endpoint for the Locative app. """
-
+    """Setup an endpoint for the Locative application."""
     # POST would be semantically better, but that currently does not work
     # since Locative sends the data as key1=value1&key2=value2
     # in the request body, while Home Assistant expects json there.
-
     hass.http.register_path(
         'GET', URL_API_LOCATIVE_ENDPOINT,
         partial(_handle_get_api_locative, hass, see))
@@ -34,8 +30,7 @@ def setup_scanner(hass, config, see):
 
 
 def _handle_get_api_locative(hass, see, handler, path_match, data):
-    """ Locative message received. """
-
+    """Locative message received."""
     if not _check_data(handler, data):
         return
 
@@ -76,6 +71,7 @@ def _handle_get_api_locative(hass, see, handler, path_match, data):
 
 
 def _check_data(handler, data):
+    """Check the data."""
     if 'latitude' not in data or 'longitude' not in data:
         handler.write_text("Latitude and longitude not specified.",
                            HTTP_UNPROCESSABLE_ENTITY)
diff --git a/homeassistant/components/device_tracker/luci.py b/homeassistant/components/device_tracker/luci.py
index 5745138bf8e0..6ee45b8fc49e 100644
--- a/homeassistant/components/device_tracker/luci.py
+++ b/homeassistant/components/device_tracker/luci.py
@@ -1,8 +1,5 @@
 """
-homeassistant.components.device_tracker.luci
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Device tracker platform that supports scanning a OpenWRT router for device
-presence.
+Support for OpenWRT routers.
 
 For more details about this platform, please refer to the documentation at
 https://home-assistant.io/components/device_tracker.luci/
@@ -20,14 +17,14 @@ from homeassistant.const import CONF_HOST, CONF_PASSWORD, CONF_USERNAME
 from homeassistant.helpers import validate_config
 from homeassistant.util import Throttle
 
-# Return cached results if last scan was less then this time ago
+# Return cached results if last scan was less then this time ago.
 MIN_TIME_BETWEEN_SCANS = timedelta(seconds=5)
 
 _LOGGER = logging.getLogger(__name__)
 
 
 def get_scanner(hass, config):
-    """ Validates config and returns a Luci scanner. """
+    """Validates configuration and returns a Luci scanner."""
     if not validate_config(config,
                            {DOMAIN: [CONF_HOST, CONF_USERNAME, CONF_PASSWORD]},
                            _LOGGER):
@@ -52,7 +49,6 @@ class LuciDeviceScanner(object):
 
     (Currently, we do only wifi iwscan, and no DHCP lease access.)
     """
-
     def __init__(self, config):
         host = config[CONF_HOST]
         username, password = config[CONF_USERNAME], config[CONF_PASSWORD]
@@ -73,14 +69,12 @@ class LuciDeviceScanner(object):
         """
         Scans for new devices and return a list containing found device ids.
         """
-
         self._update_info()
 
         return self.last_results
 
     def get_device_name(self, device):
-        """ Returns the name of the given device or None if we don't know. """
-
+        """Returns the name of the given device or None if we don't know."""
         with self.lock:
             if self.mac2name is None:
                 url = 'http://{}/cgi-bin/luci/rpc/uci'.format(self.host)
@@ -127,7 +121,7 @@ class LuciDeviceScanner(object):
 
 
 def _req_json_rpc(url, method, *args, **kwargs):
-    """ Perform one JSON RPC operation. """
+    """Perform one JSON RPC operation."""
     data = json.dumps({'method': method, 'params': args})
     try:
         res = requests.post(url, data=data, timeout=5, **kwargs)
@@ -157,6 +151,6 @@ def _req_json_rpc(url, method, *args, **kwargs):
 
 
 def _get_token(host, username, password):
-    """ Get authentication token for the given host+username+password. """
+    """Get authentication token for the given host+username+password."""
     url = 'http://{}/cgi-bin/luci/rpc/auth'.format(host)
     return _req_json_rpc(url, 'login', username, password)
diff --git a/homeassistant/components/device_tracker/mqtt.py b/homeassistant/components/device_tracker/mqtt.py
index 6fca13e6892e..d754156f2173 100644
--- a/homeassistant/components/device_tracker/mqtt.py
+++ b/homeassistant/components/device_tracker/mqtt.py
@@ -1,7 +1,5 @@
 """
-homeassistant.components.device_tracker.mqtt
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-MQTT platform for the device tracker.
+Support for tracking MQTT enabled devices.
 
 For more details about this platform, please refer to the documentation at
 https://home-assistant.io/components/device_tracker.mqtt/
@@ -22,7 +20,7 @@ _LOGGER = logging.getLogger(__name__)
 
 
 def setup_scanner(hass, config, see):
-    """ Set up a MQTT tracker. """
+    """Setup the MQTT tracker."""
     devices = config.get(CONF_DEVICES)
     qos = util.convert(config.get(CONF_QOS), int, DEFAULT_QOS)
 
@@ -34,7 +32,7 @@ def setup_scanner(hass, config, see):
     dev_id_lookup = {}
 
     def device_tracker_message_received(topic, payload, qos):
-        """ MQTT message received. """
+        """MQTT message received."""
         see(dev_id=dev_id_lookup[topic], location_name=payload)
 
     for dev_id, topic in devices.items():
diff --git a/homeassistant/components/device_tracker/netgear.py b/homeassistant/components/device_tracker/netgear.py
index eebb68c043ad..9cf7889fe524 100644
--- a/homeassistant/components/device_tracker/netgear.py
+++ b/homeassistant/components/device_tracker/netgear.py
@@ -1,8 +1,5 @@
 """
-homeassistant.components.device_tracker.netgear
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Device tracker platform that supports scanning a Netgear router for device
-presence.
+Support for Netgear routers.
 
 For more details about this platform, please refer to the documentation at
 https://home-assistant.io/components/device_tracker.netgear/
@@ -15,7 +12,7 @@ from homeassistant.components.device_tracker import DOMAIN
 from homeassistant.const import CONF_HOST, CONF_PASSWORD, CONF_USERNAME
 from homeassistant.util import Throttle
 
-# Return cached results if last scan was less then this time ago
+# Return cached results if last scan was less then this time ago.
 MIN_TIME_BETWEEN_SCANS = timedelta(seconds=5)
 
 _LOGGER = logging.getLogger(__name__)
@@ -23,7 +20,7 @@ REQUIREMENTS = ['pynetgear==0.3.2']
 
 
 def get_scanner(hass, config):
-    """ Validates config and returns a Netgear scanner. """
+    """Validates configuration and returns a Netgear scanner."""
     info = config[DOMAIN]
     host = info.get(CONF_HOST)
     username = info.get(CONF_USERNAME)
@@ -39,8 +36,7 @@ def get_scanner(hass, config):
 
 
 class NetgearDeviceScanner(object):
-    """ This class queries a Netgear wireless router using the SOAP-API. """
-
+    """Queries a Netgear wireless router using the SOAP-API."""
     def __init__(self, host, username, password):
         import pynetgear
 
@@ -74,7 +70,7 @@ class NetgearDeviceScanner(object):
         return (device.mac for device in self.last_results)
 
     def get_device_name(self, mac):
-        """ Returns the name of the given device or None if we don't know. """
+        """Returns the name of the given device or None if we don't know."""
         try:
             return next(device.name for device in self.last_results
                         if device.mac == mac)
diff --git a/homeassistant/components/device_tracker/nmap_tracker.py b/homeassistant/components/device_tracker/nmap_tracker.py
index 596986e8bb7b..823bfa69ef66 100644
--- a/homeassistant/components/device_tracker/nmap_tracker.py
+++ b/homeassistant/components/device_tracker/nmap_tracker.py
@@ -1,7 +1,5 @@
 """
-homeassistant.components.device_tracker.nmap
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Device tracker platform that supports scanning a network with nmap.
+Support for scanning a network with nmap.
 
 For more details about this platform, please refer to the documentation at
 https://home-assistant.io/components/device_tracker.nmap_scanner/
@@ -30,7 +28,7 @@ REQUIREMENTS = ['python-nmap==0.4.3']
 
 
 def get_scanner(hass, config):
-    """ Validates config and returns a Nmap scanner. """
+    """Validates configuration and returns a Nmap scanner."""
     if not validate_config(config, {DOMAIN: [CONF_HOSTS]},
                            _LOGGER):
         return None
@@ -43,7 +41,7 @@ Device = namedtuple("Device", ["mac", "name", "ip", "last_update"])
 
 
 def _arp(ip_address):
-    """ Get the MAC address for a given IP. """
+    """Get the MAC address for a given IP."""
     cmd = ['arp', '-n', ip_address]
     arp = subprocess.Popen(cmd, stdout=subprocess.PIPE)
     out, _ = arp.communicate()
@@ -55,8 +53,7 @@ def _arp(ip_address):
 
 
 class NmapDeviceScanner(object):
-    """ This class scans for devices using nmap. """
-
+    """This class scans for devices using nmap."""
     def __init__(self, config):
         self.last_results = []
 
@@ -71,14 +68,12 @@ class NmapDeviceScanner(object):
         """
         Scans for new devices and return a list containing found device ids.
         """
-
         self._update_info()
 
         return [device.mac for device in self.last_results]
 
     def get_device_name(self, mac):
-        """ Returns the name of the given device or None if we don't know. """
-
+        """Returns the name of the given device or None if we don't know."""
         filter_named = [device.name for device in self.last_results
                         if device.mac == mac]
 
diff --git a/homeassistant/components/device_tracker/owntracks.py b/homeassistant/components/device_tracker/owntracks.py
index 7ab59f952628..b8d202907b02 100644
--- a/homeassistant/components/device_tracker/owntracks.py
+++ b/homeassistant/components/device_tracker/owntracks.py
@@ -1,7 +1,5 @@
 """
-homeassistant.components.device_tracker.owntracks
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-OwnTracks platform for the device tracker.
+Support the OwnTracks platform.
 
 For more details about this platform, please refer to the documentation at
 https://home-assistant.io/components/device_tracker.owntracks/
@@ -32,13 +30,11 @@ CONF_MAX_GPS_ACCURACY = 'max_gps_accuracy'
 
 
 def setup_scanner(hass, config, see):
-    """ Set up an OwnTracks tracker. """
-
+    """Setup an OwnTracks tracker."""
     max_gps_accuracy = config.get(CONF_MAX_GPS_ACCURACY)
 
     def owntracks_location_update(topic, payload, qos):
-        """ MQTT message received. """
-
+        """MQTT message received."""
         # Docs on available data:
         # http://owntracks.org/booklet/tech/json/#_typelocation
         try:
@@ -69,8 +65,7 @@ def setup_scanner(hass, config, see):
 
     def owntracks_event_update(topic, payload, qos):
         # pylint: disable=too-many-branches, too-many-statements
-        """ MQTT event (geofences) received. """
-
+        """MQTT event (geofences) received."""
         # Docs on available data:
         # http://owntracks.org/booklet/tech/json/#_typetransition
         try:
@@ -157,8 +152,7 @@ def setup_scanner(hass, config, see):
             return
 
     def see_beacons(dev_id, kwargs_param):
-        """ Set active beacons to the current location """
-
+        """Set active beacons to the current location."""
         kwargs = kwargs_param.copy()
         # the battery state applies to the tracking device, not the beacon
         kwargs.pop('battery', None)
@@ -168,16 +162,13 @@ def setup_scanner(hass, config, see):
             see(**kwargs)
 
     mqtt.subscribe(hass, LOCATION_TOPIC, owntracks_location_update, 1)
-
     mqtt.subscribe(hass, EVENT_TOPIC, owntracks_event_update, 1)
 
     return True
 
 
 def _parse_see_args(topic, data):
-    """ Parse the OwnTracks location parameters,
-        into the format see expects. """
-
+    """Parse the OwnTracks location parameters, into the format see expects."""
     parts = topic.split('/')
     dev_id = '{}_{}'.format(parts[1], parts[2])
     host_name = parts[1]
@@ -194,8 +185,7 @@ def _parse_see_args(topic, data):
 
 
 def _set_gps_from_zone(kwargs, zone):
-    """ Set the see parameters from the zone parameters """
-
+    """Set the see parameters from the zone parameters."""
     if zone is not None:
         kwargs['gps'] = (
             zone.attributes['latitude'],
diff --git a/homeassistant/components/device_tracker/snmp.py b/homeassistant/components/device_tracker/snmp.py
index edff592f017b..f8fedfb69667 100644
--- a/homeassistant/components/device_tracker/snmp.py
+++ b/homeassistant/components/device_tracker/snmp.py
@@ -1,8 +1,5 @@
 """
-homeassistant.components.device_tracker.snmp
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Device tracker platform that supports fetching WiFi associations
-through SNMP.
+Support for fetching WiFi associations through SNMP.
 
 For more details about this platform, please refer to the documentation at
 https://home-assistant.io/components/device_tracker.snmp/
@@ -17,7 +14,7 @@ from homeassistant.const import CONF_HOST
 from homeassistant.helpers import validate_config
 from homeassistant.util import Throttle
 
-# Return cached results if last scan was less then this time ago
+# Return cached results if last scan was less then this time ago.
 MIN_TIME_BETWEEN_SCANS = timedelta(seconds=10)
 
 _LOGGER = logging.getLogger(__name__)
@@ -29,7 +26,7 @@ CONF_BASEOID = "baseoid"
 
 # pylint: disable=unused-argument
 def get_scanner(hass, config):
-    """ Validates config and returns an snmp scanner """
+    """Validates configuration and returns an snmp scanner."""
     if not validate_config(config,
                            {DOMAIN: [CONF_HOST, CONF_COMMUNITY, CONF_BASEOID]},
                            _LOGGER):
@@ -41,9 +38,7 @@ def get_scanner(hass, config):
 
 
 class SnmpScanner(object):
-    """
-    This class queries any SNMP capable Acces Point for connected devices.
-    """
+    """Queries any SNMP capable Acces Point for connected devices."""
     def __init__(self, config):
         from pysnmp.entity.rfc3413.oneliner import cmdgen
         self.snmp = cmdgen.CommandGenerator()
@@ -64,7 +59,6 @@ class SnmpScanner(object):
         """
         Scans for new devices and return a list containing found device IDs.
         """
-
         self._update_info()
         return [client['mac'] for client in self.last_results
                 if client.get('mac')]
@@ -72,7 +66,7 @@ class SnmpScanner(object):
     # Supressing no-self-use warning
     # pylint: disable=R0201
     def get_device_name(self, device):
-        """ Returns the name of the given device or None if we don't know. """
+        """Returns the name of the given device or None if we don't know."""
         # We have no names
         return None
 
@@ -94,8 +88,7 @@ class SnmpScanner(object):
             return True
 
     def get_snmp_data(self):
-        """ Fetch mac addresses from WAP via SNMP. """
-
+        """Fetch MAC addresses from WAP via SNMP."""
         devices = []
 
         errindication, errstatus, errindex, restable = self.snmp.nextCmd(
diff --git a/homeassistant/components/device_tracker/thomson.py b/homeassistant/components/device_tracker/thomson.py
index 7c7667400f56..6cd02320e3bb 100644
--- a/homeassistant/components/device_tracker/thomson.py
+++ b/homeassistant/components/device_tracker/thomson.py
@@ -1,8 +1,5 @@
 """
-homeassistant.components.device_tracker.thomson
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Device tracker platform that supports scanning a THOMSON router for device
-presence.
+Support for THOMSON routers.
 
 For more details about this platform, please refer to the documentation at
 https://home-assistant.io/components/device_tracker.thomson/
@@ -18,7 +15,7 @@ from homeassistant.const import CONF_HOST, CONF_PASSWORD, CONF_USERNAME
 from homeassistant.helpers import validate_config
 from homeassistant.util import Throttle
 
-# Return cached results if last scan was less then this time ago
+# Return cached results if last scan was less then this time ago.
 MIN_TIME_BETWEEN_SCANS = timedelta(seconds=10)
 
 _LOGGER = logging.getLogger(__name__)
@@ -35,7 +32,7 @@ _DEVICES_REGEX = re.compile(
 
 # pylint: disable=unused-argument
 def get_scanner(hass, config):
-    """ Validates config and returns a THOMSON scanner. """
+    """Validates configuration and returns a THOMSON scanner."""
     if not validate_config(config,
                            {DOMAIN: [CONF_HOST, CONF_USERNAME, CONF_PASSWORD]},
                            _LOGGER):
@@ -48,10 +45,9 @@ def get_scanner(hass, config):
 
 class ThomsonDeviceScanner(object):
     """
-    This class queries a router running THOMSON firmware
-    for connected devices. Adapted from ASUSWRT scanner.
+    This class queries a router running THOMSON firmware for connected devices.
+    Adapted from ASUSWRT scanner.
     """
-
     def __init__(self, config):
         self.host = config[CONF_HOST]
         self.username = config[CONF_USERNAME]
@@ -66,15 +62,14 @@ class ThomsonDeviceScanner(object):
         self.success_init = data is not None
 
     def scan_devices(self):
-        """ Scans for new devices and return a
-            list containing found device ids. """
-
+        """
+        Scans for new devices and return a list containing found device IDs.
+        """
         self._update_info()
         return [client['mac'] for client in self.last_results]
 
     def get_device_name(self, device):
-        """ Returns the name of the given device
-            or None if we don't know. """
+        """Returns the name of the given device or None if we don't know."""
         if not self.last_results:
             return None
         for client in self.last_results:
@@ -104,7 +99,7 @@ class ThomsonDeviceScanner(object):
             return True
 
     def get_thomson_data(self):
-        """ Retrieve data from THOMSON and return parsed result. """
+        """Retrieve data from THOMSON and return parsed result."""
         try:
             telnet = telnetlib.Telnet(self.host)
             telnet.read_until(b'Username : ')
diff --git a/homeassistant/components/device_tracker/tomato.py b/homeassistant/components/device_tracker/tomato.py
index 8f1e956dcb6b..3864fa6131d4 100644
--- a/homeassistant/components/device_tracker/tomato.py
+++ b/homeassistant/components/device_tracker/tomato.py
@@ -1,8 +1,5 @@
 """
-homeassistant.components.device_tracker.tomato
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Device tracker platform that supports scanning a Tomato router for device
-presence.
+Support for Tomato routers.
 
 For more details about this platform, please refer to the documentation at
 https://home-assistant.io/components/device_tracker.tomato/
@@ -20,7 +17,7 @@ from homeassistant.const import CONF_HOST, CONF_PASSWORD, CONF_USERNAME
 from homeassistant.helpers import validate_config
 from homeassistant.util import Throttle
 
-# Return cached results if last scan was less then this time ago
+# Return cached results if last scan was less then this time ago.
 MIN_TIME_BETWEEN_SCANS = timedelta(seconds=5)
 
 CONF_HTTP_ID = "http_id"
@@ -29,7 +26,7 @@ _LOGGER = logging.getLogger(__name__)
 
 
 def get_scanner(hass, config):
-    """ Validates config and returns a Tomato scanner. """
+    """Validates configuration and returns a Tomato scanner."""
     if not validate_config(config,
                            {DOMAIN: [CONF_HOST, CONF_USERNAME,
                                      CONF_PASSWORD, CONF_HTTP_ID]},
@@ -40,13 +37,12 @@ def get_scanner(hass, config):
 
 
 class TomatoDeviceScanner(object):
-    """ This class queries a wireless router running Tomato firmware
+    """This class queries a wireless router running Tomato firmware
     for connected devices.
 
     A description of the Tomato API can be found on
     http://paulusschoutsen.nl/blog/2013/10/tomato-api-documentation/
     """
-
     def __init__(self, config):
         host, http_id = config[CONF_HOST], config[CONF_HTTP_ID]
         username, password = config[CONF_USERNAME], config[CONF_PASSWORD]
@@ -68,16 +64,15 @@ class TomatoDeviceScanner(object):
         self.success_init = self._update_tomato_info()
 
     def scan_devices(self):
-        """ Scans for new devices and return a
-            list containing found device ids. """
-
+        """
+        Scans for new devices and return a list containing found device IDs.
+        """
         self._update_tomato_info()
 
         return [item[1] for item in self.last_results['wldev']]
 
     def get_device_name(self, device):
-        """ Returns the name of the given device or None if we don't know. """
-
+        """Returns the name of the given device or None if we don't know."""
         filter_named = [item[0] for item in self.last_results['dhcpd_lease']
                         if item[2] == device]
 
@@ -88,19 +83,16 @@ class TomatoDeviceScanner(object):
 
     @Throttle(MIN_TIME_BETWEEN_SCANS)
     def _update_tomato_info(self):
-        """ Ensures the information from the Tomato router is up to date.
-            Returns boolean if scanning successful. """
-
+        """Ensures the information from the Tomato router is up to date.
+        Returns boolean if scanning successful.
+        """
         with self.lock:
             self.logger.info("Scanning")
 
             try:
                 response = requests.Session().send(self.req, timeout=3)
-
                 # Calling and parsing the Tomato api here. We only need the
-                # wldev and dhcpd_lease values. For API description see:
-                # http://paulusschoutsen.nl/
-                #   blog/2013/10/tomato-api-documentation/
+                # wldev and dhcpd_lease values.
                 if response.status_code == 200:
 
                     for param, value in \
@@ -109,7 +101,6 @@ class TomatoDeviceScanner(object):
                         if param == 'wldev' or param == 'dhcpd_lease':
                             self.last_results[param] = \
                                 json.loads(value.replace("'", '"'))
-
                     return True
 
                 elif response.status_code == 401:
@@ -117,29 +108,25 @@ class TomatoDeviceScanner(object):
                     self.logger.exception((
                         "Failed to authenticate, "
                         "please check your username and password"))
-
                     return False
 
             except requests.exceptions.ConnectionError:
                 # We get this if we could not connect to the router or
-                # an invalid http_id was supplied
+                # an invalid http_id was supplied.
                 self.logger.exception((
                     "Failed to connect to the router"
                     " or invalid http_id supplied"))
-
                 return False
 
             except requests.exceptions.Timeout:
                 # We get this if we could not connect to the router or
-                # an invalid http_id was supplied
+                # an invalid http_id was supplied.
                 self.logger.exception(
                     "Connection to the router timed out")
-
                 return False
 
             except ValueError:
-                # If json decoder could not parse the response
+                # If JSON decoder could not parse the response.
                 self.logger.exception(
                     "Failed to parse response from router")
-
                 return False
diff --git a/homeassistant/components/device_tracker/ubus.py b/homeassistant/components/device_tracker/ubus.py
index 073588008b03..1c508f0026b5 100644
--- a/homeassistant/components/device_tracker/ubus.py
+++ b/homeassistant/components/device_tracker/ubus.py
@@ -1,8 +1,5 @@
 """
-homeassistant.components.device_tracker.ubus
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Device tracker platform that supports scanning a OpenWRT router for device
-presence.
+Support for OpenWRT (ubus) routers.
 
 For more details about this platform, please refer to the documentation at
 https://home-assistant.io/components/device_tracker.ubus/
@@ -20,14 +17,14 @@ from homeassistant.const import CONF_HOST, CONF_PASSWORD, CONF_USERNAME
 from homeassistant.helpers import validate_config
 from homeassistant.util import Throttle
 
-# Return cached results if last scan was less then this time ago
+# Return cached results if last scan was less then this time ago.
 MIN_TIME_BETWEEN_SCANS = timedelta(seconds=5)
 
 _LOGGER = logging.getLogger(__name__)
 
 
 def get_scanner(hass, config):
-    """ Validates config and returns a Luci scanner. """
+    """Validates configuration and returns a Luci scanner."""
     if not validate_config(config,
                            {DOMAIN: [CONF_HOST, CONF_USERNAME, CONF_PASSWORD]},
                            _LOGGER):
@@ -74,16 +71,13 @@ class UbusDeviceScanner(object):
 
     def scan_devices(self):
         """
-        Scans for new devices and return a list containing found device ids.
+        Scans for new devices and return a list containing found device IDs.
         """
-
         self._update_info()
-
         return self.last_results
 
     def get_device_name(self, device):
-        """ Returns the name of the given device or None if we don't know. """
-
+        """Returns the name of the given device or None if we don't know."""
         with self.lock:
             if self.leasefile is None:
                 result = _req_json_rpc(self.url, self.session_id,
@@ -141,8 +135,7 @@ class UbusDeviceScanner(object):
 
 
 def _req_json_rpc(url, session_id, rpcmethod, subsystem, method, **params):
-    """ Perform one JSON RPC operation. """
-
+    """Perform one JSON RPC operation."""
     data = json.dumps({"jsonrpc": "2.0",
                        "id": 1,
                        "method": rpcmethod,
@@ -167,7 +160,7 @@ def _req_json_rpc(url, session_id, rpcmethod, subsystem, method, **params):
 
 
 def _get_session_id(url, username, password):
-    """ Get authentication token for the given host+username+password. """
+    """Get the authentication token for the given host+username+password."""
     res = _req_json_rpc(url, "00000000000000000000000000000000", 'call',
                         'session', 'login', username=username,
                         password=password)
diff --git a/homeassistant/components/device_tracker/unifi.py b/homeassistant/components/device_tracker/unifi.py
index 24dd8e7db001..931960eafe46 100644
--- a/homeassistant/components/device_tracker/unifi.py
+++ b/homeassistant/components/device_tracker/unifi.py
@@ -1,7 +1,8 @@
 """
-homeassistant.components.device_tracker.unifi
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Device tracker platform that supports scanning a Unifi WAP controller
+Support for Unifi WAP controllers.
+
+For more details about this platform, please refer to the documentation at
+https://home-assistant.io/components/device_tracker.unifi/
 """
 import logging
 import urllib
@@ -17,7 +18,7 @@ CONF_PORT = 'port'
 
 
 def get_scanner(hass, config):
-    """ Sets up unifi device_tracker """
+    """Setup Unifi device_tracker."""
     from unifi.controller import Controller
 
     if not validate_config(config, {DOMAIN: [CONF_USERNAME,
@@ -48,7 +49,6 @@ def get_scanner(hass, config):
 
 class UnifiScanner(object):
     """Provide device_tracker support from Unifi WAP client data."""
-
     def __init__(self, controller):
         self._controller = controller
         self._update()
@@ -63,12 +63,12 @@ class UnifiScanner(object):
         self._clients = {client['mac']: client for client in clients}
 
     def scan_devices(self):
-        """ Scans for devices. """
+        """Scans for devices."""
         self._update()
         return self._clients.keys()
 
     def get_device_name(self, mac):
-        """ Returns the name (if known) of the device.
+        """Returns the name (if known) of the device.
 
         If a name has been set in Unifi, then return that, else
         return the hostname if it has been detected.