Broadcast Receiver

Manifest.permission https://developer.android.com/reference/android/Manifest.permission

What triggers the BluetoothDevice.ACTION_ACL broadcasts? https://stackoverflow.com/questions/9537833/what-triggers-the-bluetoothdevice-action-acl-broadcasts

Creating BroadcastReceivers that Run while Your Android App Is Backgrounded https://spin.atomicobject.com/2017/10/16/broadcast-receivers-android-background/

Very helpful: Android Broadcast Receiver bluetooth events catching https://stackoverflow.com/questions/30222409/android-broadcast-receiver-bluetooth-events-catching

Starting Background Services https://guides.codepath.com/android/starting-background-services

Is it possible to implement a broadcastreceiver with BLE? https://stackoverflow.com/questions/21306760/is-it-possible-to-implement-a-broadcastreceiver-with-ble

I will add more links from my research and everyone's research later.