Android is an operating system that is in use in many types of mobile phones, tablets, and other devices.

Android applications are traditionally developed with the Java programming language. Another suitable programming language is Kotlin, that is recommended by Google. In addition to Java or Kotlin, you must learn some XML, which is used to specify user interfaces for Android applications.

This page provides some links that should be useful when you learn to develop applications (apps) for Android-based devices.

Some Android videos in English: