app should not close or go in background
I want to use android for a single application only. 

Means this application will always running and visible for user interaction, it should not close or go in background and also should not allow user to access other application without permission from this application.
app should not close or go in background
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I want to use android for a single application only. 

Means this application will always running and visible for user interaction, it should not close or go in background and also should not allow user to access other application without permission from this application.