How to open apk files

On Windows you have to rename it to ZIP and extract.

On Linux just right click on APK and extract it. Linux recognizes it as an archive file by default.

On Mac, I had issues with renaming so I extract file via Terminal by using the command unzip xyz.apk -d apkDir (it will extract into apkDir directory)

You will then see encrypted Java and XML files which you cannot open (without some extra effort). But you will be able to see and open files from /assets.

APK files are meant to be used by the Android OS to install an application. If you want to use one on an android phone/simulator, use "adb install something.apk" from the terminal/command line. Alternatively, you could email the apk to yourself, then open your email on the device and open the attachment.

APK files are basically just a wrapper around an app, you can also open one in a program like WinRAR or some other unzipping/decompression program on your computer to view their contents.