To have a gist over the application context and activity context read below:
The application context will live as long as your application is alive and does not depend on the activities life cycle. If you plan on keeping long-lived objects that need a context, remember the application object. You can obtain it easily by calling Context.getApplicationContext() or Activity.getApplication().
In summary, to avoid context-related memory leaks, remember the following:
1.Do not keep long-lived references to a context-activity (a reference to an activity should have the same life cycle as the activity itself)
2.Try using the context-application instead of a context-activity
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