As is the case with many file formats, APK files can have any name needed, but it may be required that the file name ends in the file extension for being recognized as such. dex files), resources, assets, certificates, and manifest file. An APK file contains all of a program's code (such as. To make an APK file, a program for Android is first compiled using a tool such as Android Studio or Visual Studio and then all of its parts are packaged into one container file. APK is analogous to other software packages such as APPX in Microsoft Windows or a Debian package in Debian-based operating systems.