Working build of App - can use dpad not just centre button

README.md

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+![bthome app](screenshots/bthome_app.png)
+
+This application turns the Flipper Zero into a [BTHome](https://bthome.io)
+beacon, and can be used to integrate the Flipper with home automation systems
+that support BTHome, such as Home Assistant.
+
+[BTHome](https://bthome.io) is an open standard for broadcasting sensor data
+over Bluetooth Low Energy (BLE). It allows devices to transmit sensor readings
+(temperature, humidity, battery level, button events, etc.) without requiring
+pairing or an active connection.
+
+The BTHome beacon is triggered when pressing the Flipper Zero "OK" button
+and currently includes the Flipper's battery percentage as a sensor.
+
+Unfortunately, due to the limited size of BLE packets the Flipper Zero can send
+there isn't much room left to add more sensors without removing the existing
+one.
+
+### Home Assistant setup
+
+The first step is setting up the [BTHome](https://www.home-assistant.io/integrations/bthome/) integration in Home Assistant.
+
+Once setup, the Flipper should be automatically discovered after pressing the
+center button once:
+
+![home assistant discovered](screenshots/home_assistant_discovered.png)
+
+The device's page will then show the current battery status and its events:
+
+![home assistant paired](screenshots/home_assistant_paired.png)