Release Memory of Particular Activity when it is Destroyed

Question

I have a launcher Activity that load and resize big bitmap as it\'s background when it opens.

Whenever hit the back button, the Activity is

Answer 1

In activity if you're calling the finish() method from is destroyed and all its resources are queued for garbage collection.

So, all memory that was used by this activity will be freed during next GC cycle.

OR

you can try this to clean memory,

@Override
public void onDestroy() {
    super.onDestroy();
    Runtime.getRuntime().gc();      
}

check this details. hope that helps.