app is not working after apk installation

[Mohamed_Tamer]

Hi @funtu,
First you are not switching screen correctly.See here:

How to switch screens correctly

I see many issues done by users because they switched screens not correct. This below is now just one of many other solutions: [blocks] If you dont open/close screens correct your app will get possible runtime errors. Possible errors: (example) Unable to add window -- token android.os.BinderProxy@45d459c0 is not valid; is your activity running? Iam sure you don’t want that. Then please do it in the future and switch screens correct. General Tips and Tricks for App Inventor/Makeroid …

@funtu

but if screen 1 is closed by pressing mobile home button, then it takes double tap on app icon to open screen 1 again.

You can see here:

Having a bug in reopening app after closing it

i know this bug it happened with me before…You must do two things first close screens properly…Second, use close screen instead of closing application…It will work well…