Want the instance for iOS/android supply code for robotically touching

I wish to construct an software (iOS/android) that may run in background and do the touching to the coordinates what I’ve set as a situation.

I can describe concerning the App by steps beneath:

1. Open App and see the display screen with button Begin -> Click on Begin button
2. After that the app might be in background
3. The App auto contact to a different app (I known as it App A) in display screen by the coordinates what I’ve already set
4. The one other app might be open
5. The App proceed auto contact to a textfield on App A by the Coordinates too

If anybody have expertise for that, please assist me the options or the instance supply code.

Many thanks.