How to open an APK file in Ubuntu 18.04?

I'm trying to inspect an APK of an Android app I'm developing. I was able to open and decompress APK files using the Archive Manager application (file-roller, the standard app for compressed files), but I don't know if it's because of the latest Android Studio IDE changes or if it has to do with Ubuntu 18.04 that now I can't.

If I try to open an APK file with this Archive Manger I fails with a dialog saying:

Could not open "app-debug.apk"

Archive type not supported.


Workaround: copy [whatever].apk to [whatever].zip

cp whatever.apk whatever.zip

Then Archive Manager will work with the .zip version

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Apktool

It is the perfect tool for opening and analyzing apk files, and it is cross-platform and open source :D