build me an android application

I need a developer to build me an android phone application that changes the lock screen image every five seconds with a counter of 5 seconds displayed on the Lock Screen
-I need the images to get fetched from the cloud (firebase preferred)
-I need the Lock Screen to get back to the user's regular Lock Screen if no images are left
-I need a counter of 5 seconds displayed in the Lock Screen
-all these features should happen at the same lock screen as the user's(the user can then open their phone with their regular password).
- I need a feedback if the user finished the 5 second or not .