mt manager is one of the most popular APK file editors for Android. To take full advantage of this app, you'll need to have root permissions. With superuser permissions, you will be able to modify user and system apps. When editing these apps, you can edit Dex, ARSC and XML code, as well as optimize, clone and sign apps, remove verifications and even add translations. Thus, you can delete unnecessary files from an app and gain storage space.