Exit android app on back pressed

Question

I am building an Android App. How to exit an Android App when back is pressed. Android version is 2.3.3 and above. The Android App goes to previous activity which i don\'t want.

Answer 1

// Finish current activity
// Go back to previous activity or closes app if last activity
finish()

// Finish all activities in stack and app closes
finishAffinity()

// Takes you to home screen but app isnt closed 
// Opening app takes you back to this current activity (if it hasnt been destroyed)
Intent(Intent.ACTION_MAIN).apply {  
    addCategory(Intent.CATEGORY_HOME)
    flags = Intent.FLAG_ACTIVITY_NEW_TASK
    startActivity(this)
}