Where are the entry points of a program usually located in the code?

In Android applications, the entry point of the program is usually located in a class that inherits from Application or in the main Activity.

• Application Class — created once when the application starts and initializes global settings and dependencies.
• MainActivity — the first activity that is launched and displayed to the user.

In the Android manifest (AndroidManifest.xml), it is specified which Activity is the main one using an intent filter:

<intent-filter>
    <action android:name="android.intent.action.MAIN" />
    <category android:name="android.intent.category.LAUNCHER" />
</intent-filter>

Thus, the entry point is the onCreate() method in MainActivity or in the Application class, where the application's logic begins.