Dear sir. I’m a android app developer and have rich experience. I have developed similar apps match to your needs and I can customize it.
I can make webservices and integrate into android app.
I can make push notificaion and use for any alert in the app.
I can make screen the same as the graphic resources.
I can use ffmpeg lib to play audio and video on mobile phone.
You can search "uSearch" on playstore. this the app that I have made.
If you interest me please contact me.
Thanks.