The difficulties to learn Android programming online:

• The most crucial aspect of Android development is app design. You must create programmes that are compatible with all or almost all of the world's displays. The screen resolution is not the only factor to consider; you must also consider the OS versions.
• To display one window, you must produce numerous files, such as a product display page for end users, but three XML files and at least two Java files for developers. Developers, particularly those who have transitioned from.NET to Android, will undoubtedly face significant difficulties.
• Because you can't rely on one screen or one version of Android, you must test each update on a variety of devices, including brands and sizes.
• When creating an Android application, developers must ensure that it is compatible with all Android devices. Before launching the app on the Google Play store, all functions, including as the camera, keyboard modifications, size, and storage, must be thoroughly tested.

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