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    <p>Very interesting question. I think it's mainly a semantic meaning, and may also be due to historical reasons.</p> <p>Although in current Android Activity and Service implementations, <code>getApplication()</code> and <code>getApplicationContext()</code> return the same object, there is no guarantee that this will always be the case (for example, in a specific vendor implementation).</p> <p>So if you want the Application class you registered in the Manifest, you should <strong>never</strong> call <code>getApplicationContext()</code> and cast it to your application, because it may not be the application instance (which you obviously experienced with the test framework).</p> <p>Why does <code>getApplicationContext()</code> exist in the first place ?</p> <p><code>getApplication()</code> is only available in the Activity class and the Service class, whereas <code>getApplicationContext()</code> is declared in the Context class.</p> <p>That actually means one thing : when writing code in a broadcast receiver, which is not a context but is given a context in its onReceive method, you can only call <code>getApplicationContext()</code>. Which also means that you are not guaranteed to have access to your application in a BroadcastReceiver.</p> <p>When looking at the Android code, you see that when attached, an activity receives a base context and an application, and those are different parameters. <code>getApplicationContext()</code> delegates it's call to <code>baseContext.getApplicationContext()</code>.</p> <p>One more thing : the documentation says that it most cases, you shouldn't need to subclass Application: </p> <blockquote> <p>There is normally no need to subclass <code>Application</code>. In most situation, static singletons can provide the same functionality in a more modular way. If your singleton needs a global context (for example to register broadcast receivers), the function to retrieve it can be given a <code>Context</code> which internally uses <code>Context.getApplicationContext()</code> when first constructing the singleton.</p> </blockquote> <p>I know this is not an exact and precise answer, but still, does that answer your question?</p>
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    1. CO@Piwaï: Don't listen to the doc. Subclassing `android.app.Application` is super help full. For example I had endless problems initializing the database. Once moved into `Application.onCreate` it worked like a charm. Now I do all system wide initialisation in `Application` and I would not write another App without.
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