diff --git a/homeassistant/components/mobile_app/binary_sensor.py b/homeassistant/components/mobile_app/binary_sensor.py
index d9d766974fd..4d40e42a47e 100644
--- a/homeassistant/components/mobile_app/binary_sensor.py
+++ b/homeassistant/components/mobile_app/binary_sensor.py
@@ -1,4 +1,6 @@
 """Binary sensor platform for mobile_app."""
+from typing import Any
+
 from homeassistant.components.binary_sensor import BinarySensorEntity
 from homeassistant.config_entries import ConfigEntry
 from homeassistant.const import CONF_NAME, CONF_UNIQUE_ID, CONF_WEBHOOK_ID, STATE_ON
@@ -18,7 +20,6 @@ from .const import (
     ATTR_SENSOR_TYPE,
     ATTR_SENSOR_TYPE_BINARY_SENSOR as ENTITY_TYPE,
     ATTR_SENSOR_UNIQUE_ID,
-    DATA_DEVICES,
     DOMAIN,
 )
 from .entity import MobileAppEntity, unique_id
@@ -39,7 +40,7 @@ async def async_setup_entry(
     for entry in entries:
         if entry.domain != ENTITY_TYPE or entry.disabled_by:
             continue
-        config = {
+        config: dict[str, Any] = {
             ATTR_SENSOR_ATTRIBUTES: {},
             ATTR_SENSOR_DEVICE_CLASS: entry.device_class or entry.original_device_class,
             ATTR_SENSOR_ICON: entry.original_icon,
@@ -49,7 +50,7 @@ async def async_setup_entry(
             ATTR_SENSOR_UNIQUE_ID: entry.unique_id,
             ATTR_SENSOR_ENTITY_CATEGORY: entry.entity_category,
         }
-        entities.append(MobileAppBinarySensor(config, entry.device_id, config_entry))
+        entities.append(MobileAppBinarySensor(config, config_entry))
 
     async_add_entities(entities)
 
@@ -65,9 +66,7 @@ async def async_setup_entry(
             CONF_NAME
         ] = f"{config_entry.data[ATTR_DEVICE_NAME]} {data[ATTR_SENSOR_NAME]}"
 
-        device = hass.data[DOMAIN][DATA_DEVICES][data[CONF_WEBHOOK_ID]]
-
-        async_add_entities([MobileAppBinarySensor(data, device, config_entry)])
+        async_add_entities([MobileAppBinarySensor(data, config_entry)])
 
     async_dispatcher_connect(
         hass,
diff --git a/homeassistant/components/mobile_app/device_action.py b/homeassistant/components/mobile_app/device_action.py
index 3ad43098225..d17702ec24f 100644
--- a/homeassistant/components/mobile_app/device_action.py
+++ b/homeassistant/components/mobile_app/device_action.py
@@ -7,6 +7,7 @@ from homeassistant.components import notify
 from homeassistant.components.device_automation import InvalidDeviceAutomationConfig
 from homeassistant.const import CONF_DEVICE_ID, CONF_DOMAIN, CONF_TYPE
 from homeassistant.core import Context, HomeAssistant
+from homeassistant.exceptions import TemplateError
 from homeassistant.helpers import config_validation as cv, template
 
 from .const import DOMAIN
@@ -62,7 +63,7 @@ async def async_call_action_from_config(
 
         try:
             service_data[key] = template.render_complex(value_template, variables)
-        except template.TemplateError as err:
+        except TemplateError as err:
             raise InvalidDeviceAutomationConfig(
                 f"Error rendering {key}: {err}"
             ) from err
diff --git a/homeassistant/components/mobile_app/device_tracker.py b/homeassistant/components/mobile_app/device_tracker.py
index 67f3672ef8d..5e2ae23af16 100644
--- a/homeassistant/components/mobile_app/device_tracker.py
+++ b/homeassistant/components/mobile_app/device_tracker.py
@@ -37,7 +37,6 @@ async def async_setup_entry(
     """Set up OwnTracks based off an entry."""
     entity = MobileAppEntity(entry)
     async_add_entities([entity])
-    return True
 
 
 class MobileAppEntity(TrackerEntity, RestoreEntity):
diff --git a/homeassistant/components/mobile_app/entity.py b/homeassistant/components/mobile_app/entity.py
index 0c26533b7cb..0cb6cfc6fcc 100644
--- a/homeassistant/components/mobile_app/entity.py
+++ b/homeassistant/components/mobile_app/entity.py
@@ -1,4 +1,6 @@
 """A entity class for mobile_app."""
+from __future__ import annotations
+
 from homeassistant.config_entries import ConfigEntry
 from homeassistant.const import (
     ATTR_ICON,
@@ -8,7 +10,6 @@ from homeassistant.const import (
     STATE_UNAVAILABLE,
 )
 from homeassistant.core import callback
-from homeassistant.helpers.device_registry import DeviceEntry
 from homeassistant.helpers.dispatcher import async_dispatcher_connect
 from homeassistant.helpers.restore_state import RestoreEntity
 
@@ -33,10 +34,9 @@ def unique_id(webhook_id, sensor_unique_id):
 class MobileAppEntity(RestoreEntity):
     """Representation of an mobile app entity."""
 
-    def __init__(self, config: dict, device: DeviceEntry, entry: ConfigEntry) -> None:
+    def __init__(self, config: dict, entry: ConfigEntry) -> None:
         """Initialize the entity."""
         self._config = config
-        self._device = device
         self._entry = entry
         self._registration = entry.data
         self._unique_id = config[CONF_UNIQUE_ID]
diff --git a/homeassistant/components/mobile_app/helpers.py b/homeassistant/components/mobile_app/helpers.py
index c4e0a81560b..b7d38357a78 100644
--- a/homeassistant/components/mobile_app/helpers.py
+++ b/homeassistant/components/mobile_app/helpers.py
@@ -60,7 +60,7 @@ def setup_encrypt() -> tuple[int, Callable]:
     return (SecretBox.KEY_SIZE, encrypt)
 
 
-def _decrypt_payload(key: str, ciphertext: str) -> dict[str, str]:
+def _decrypt_payload(key: str | None, ciphertext: str) -> dict[str, str] | None:
     """Decrypt encrypted payload."""
     try:
         keylen, decrypt = setup_decrypt()
@@ -72,13 +72,13 @@ def _decrypt_payload(key: str, ciphertext: str) -> dict[str, str]:
         _LOGGER.warning("Ignoring encrypted payload because no decryption key known")
         return None
 
-    key = key.encode("utf-8")
-    key = key[:keylen]
-    key = key.ljust(keylen, b"\0")
+    key_bytes = key.encode("utf-8")
+    key_bytes = key_bytes[:keylen]
+    key_bytes = key_bytes.ljust(keylen, b"\0")
 
     try:
-        message = decrypt(ciphertext, key)
-        message = json.loads(message.decode("utf-8"))
+        msg_bytes = decrypt(ciphertext, key_bytes)
+        message = json.loads(msg_bytes.decode("utf-8"))
         _LOGGER.debug("Successfully decrypted mobile_app payload")
         return message
     except ValueError:
diff --git a/homeassistant/components/mobile_app/http_api.py b/homeassistant/components/mobile_app/http_api.py
index a80e7db204e..20fa25ec21f 100644
--- a/homeassistant/components/mobile_app/http_api.py
+++ b/homeassistant/components/mobile_app/http_api.py
@@ -4,6 +4,7 @@ from __future__ import annotations
 from contextlib import suppress
 from http import HTTPStatus
 import secrets
+from typing import cast
 
 from aiohttp.web import Request, Response
 import emoji
@@ -89,7 +90,7 @@ class RegistrationsView(HomeAssistantView):
             # If otherwise empty string contains emoji
             # use descriptive name of the first emoji
             data[ATTR_DEVICE_NAME] = emoji.demojize(
-                emoji.emoji_lis(data[ATTR_DEVICE_NAME])[0]["emoji"]
+                cast(str, emoji.emoji_lis(data[ATTR_DEVICE_NAME])[0]["emoji"])
             ).replace(":", "")
         else:
             # Fallback to DEVICE_ID
diff --git a/homeassistant/components/mobile_app/push_notification.py b/homeassistant/components/mobile_app/push_notification.py
index f3852895d32..0ef9739c8bd 100644
--- a/homeassistant/components/mobile_app/push_notification.py
+++ b/homeassistant/components/mobile_app/push_notification.py
@@ -28,7 +28,7 @@ class PushChannel:
         self.support_confirm = support_confirm
         self._send_message = send_message
         self.on_teardown = on_teardown
-        self.pending_confirms = {}
+        self.pending_confirms: dict[str, dict] = {}
 
     @callback
     def async_send_notification(self, data, fallback_send):
diff --git a/homeassistant/components/mobile_app/sensor.py b/homeassistant/components/mobile_app/sensor.py
index 32477ccb50a..45bc4acd6a2 100644
--- a/homeassistant/components/mobile_app/sensor.py
+++ b/homeassistant/components/mobile_app/sensor.py
@@ -1,6 +1,8 @@
 """Sensor platform for mobile_app."""
 from __future__ import annotations
 
+from typing import Any
+
 from homeassistant.components.sensor import SensorDeviceClass, SensorEntity
 from homeassistant.config_entries import ConfigEntry
 from homeassistant.const import (
@@ -28,7 +30,6 @@ from .const import (
     ATTR_SENSOR_TYPE_SENSOR as ENTITY_TYPE,
     ATTR_SENSOR_UNIQUE_ID,
     ATTR_SENSOR_UOM,
-    DATA_DEVICES,
     DOMAIN,
 )
 from .entity import MobileAppEntity, unique_id
@@ -49,7 +50,7 @@ async def async_setup_entry(
     for entry in entries:
         if entry.domain != ENTITY_TYPE or entry.disabled_by:
             continue
-        config = {
+        config: dict[str, Any] = {
             ATTR_SENSOR_ATTRIBUTES: {},
             ATTR_SENSOR_DEVICE_CLASS: entry.device_class or entry.original_device_class,
             ATTR_SENSOR_ICON: entry.original_icon,
@@ -60,7 +61,7 @@ async def async_setup_entry(
             ATTR_SENSOR_UOM: entry.unit_of_measurement,
             ATTR_SENSOR_ENTITY_CATEGORY: entry.entity_category,
         }
-        entities.append(MobileAppSensor(config, entry.device_id, config_entry))
+        entities.append(MobileAppSensor(config, config_entry))
 
     async_add_entities(entities)
 
@@ -76,9 +77,7 @@ async def async_setup_entry(
             CONF_NAME
         ] = f"{config_entry.data[ATTR_DEVICE_NAME]} {data[ATTR_SENSOR_NAME]}"
 
-        device = hass.data[DOMAIN][DATA_DEVICES][data[CONF_WEBHOOK_ID]]
-
-        async_add_entities([MobileAppSensor(data, device, config_entry)])
+        async_add_entities([MobileAppSensor(data, config_entry)])
 
     async_dispatcher_connect(
         hass,
diff --git a/mypy.ini b/mypy.ini
index adb0cb25297..3f8386a2a27 100644
--- a/mypy.ini
+++ b/mypy.ini
@@ -2477,27 +2477,6 @@ ignore_errors = true
 [mypy-homeassistant.components.minecraft_server.sensor]
 ignore_errors = true
 
-[mypy-homeassistant.components.mobile_app.binary_sensor]
-ignore_errors = true
-
-[mypy-homeassistant.components.mobile_app.device_action]
-ignore_errors = true
-
-[mypy-homeassistant.components.mobile_app.device_tracker]
-ignore_errors = true
-
-[mypy-homeassistant.components.mobile_app.helpers]
-ignore_errors = true
-
-[mypy-homeassistant.components.mobile_app.http_api]
-ignore_errors = true
-
-[mypy-homeassistant.components.mobile_app.push_notification]
-ignore_errors = true
-
-[mypy-homeassistant.components.mobile_app.sensor]
-ignore_errors = true
-
 [mypy-homeassistant.components.netgear]
 ignore_errors = true
 
diff --git a/script/hassfest/mypy_config.py b/script/hassfest/mypy_config.py
index 8d542290458..ef29562578e 100644
--- a/script/hassfest/mypy_config.py
+++ b/script/hassfest/mypy_config.py
@@ -94,13 +94,6 @@ IGNORED_MODULES: Final[list[str]] = [
     "homeassistant.components.minecraft_server",
     "homeassistant.components.minecraft_server.helpers",
     "homeassistant.components.minecraft_server.sensor",
-    "homeassistant.components.mobile_app.binary_sensor",
-    "homeassistant.components.mobile_app.device_action",
-    "homeassistant.components.mobile_app.device_tracker",
-    "homeassistant.components.mobile_app.helpers",
-    "homeassistant.components.mobile_app.http_api",
-    "homeassistant.components.mobile_app.push_notification",
-    "homeassistant.components.mobile_app.sensor",
     "homeassistant.components.netgear",
     "homeassistant.components.netgear.config_flow",
     "homeassistant.components.netgear.device_tracker",