Describe the process of starting an Android application and its initiation stages.

The process of starting an Android application involves several stages:

1. Application process launch — Android system creates a new process for the app if it is not already running.
2. Initialization of the Application class — an instance of the class that extends Application is created, where global initialization can be performed.
3. Launching the main Activity — the system calls the onCreate() method of the main Activity specified in the manifest as LAUNCHER.
4. Activity lifecycle — methods onStart(), onResume() are called, after which the Activity becomes visible and interactive.

Thus, app startup is the creation of a process, initialization of global components, launching the UI through Activity, and transitioning to an active state.

Example: when the user launches the app, they see a screen created in the onCreate() method of the main Activity.