APK (Android Package Kit) files are the standard format the Android operating system uses to distribute and install mobile applications. An APK contains all the components necessary to run an app on an Android device, including code, images, audio, and video. For example, the apps users download from Google Play Store are typically downloaded as an APK file.
An APK is essential for Android developers as it helps save time on developing apps and reduces code maintenance. Furthermore, APKs improve the app’s overall performance.
One of the most efficient strategies when developing an application for the APK is creating different build variants. Build variants are modifications of an app that target specific devices or user groups, which helps extend its reach and guarantee support for a wide variety of users.
APK files can be downloaded and installed from sources other than the Google Play Store, but caution should be exercised when installing APKs from unknown sources as they may contain malware or other security risks. A mobile security best practice is to only download applications from trustworthy sources such as the Google Play Store.