But here’s the catch: For a long time, InCallUI was a tightly guarded, OEM-specific application. With the introduction of the Telecom framework and ConnectionService APIs, Google attempted to standardize it. Yet, the reality remains messy.
adb shell am force-stop com.android.dialer adb shell am start -a android.intent.action.ANSWER If the phone still rings but you can't see the UI, you've replicated a core Telecom bug. With Android 14, Google doubled down on "cross-device calling" (Call Streaming). This introduces a new layer: RemoteInCallService .
Trying to overlay a Dialog on top of the system InCallUI. This never works reliably due to SYSTEM_ALERT_WINDOW restrictions and the fact that the system InCallUI has the highest priority ( TYPE_APPLICATION_OVERLAY is lower than TYPE_PHONE ).
Now, your Android tablet can show an InCallUI for a call active on your phone. This is implemented via a new InCallService extension that proxies touch events (mute, speaker) back to the phone over Bluetooth LE.