Android TelephonyManager App with Video Overlay

I'm seeking an experienced Android developer to create a native app utilizing the TelephonyManager. This app should be able to show an overlay when an outgoing call is made from the dialer, and subsequently close the overlay when the call is answered on the other end.

Key Requirements:
- The overlay should auto-play a video when an outgoing call is made.
- The overlay should completely close when the call is answered.
- The video should be played without any user interaction.

Ideal Skills:
- Proficient in Android app development.
- Familiar with TelephonyManager and overlay creation.
- Experience with video playback within an app.

Please note, this project does not require any video calling features or user interaction with the video. The focus is on seamless integration with the dialer and automatic video playback during the call.