As the name suggests, APK Editor is an app that allows users to edit APK files. APK (Android Application Package) files are files that contain the information for an Android or Android-based application. By modifying the APK file, you can change aspects of an application and store the APK so that your modified version is ready to install whenever you need it.
In a typical situation, modifications to an APK would have to be done using the source files and the Android SDK, and then tested in an emulator like YouWave for convenience. With APK Editor, the user can edit from your Android device.
Simple editing and user interface
APK Editor gives the user two options; simple edit and full edit. Simple edit allows the user to make changes inside the APK, such as replacing certain files. This could be used to change the images used in the app, for example. Full edit completely rebuilds the files from the APK, giving you much more control over what you can do with it.
Both modes are very easy to use, though full edit mode is considerably more strenuous on the device, and should only be used by advanced users who know their way around the insides of an APK file. There is documentation to help you along, but it is a little limited. It should be fine for a beginner to use simple edit.
Easy to use, difficult to master
The simple user interface makes it clear what the user is editing. APK Editor even presents the user with a list of available apps on the device, making it easy to find the one you want to edit. Changing basic files and app data is easy enough that even beginners should find it a simple task.
However, while the full edit option is easy enough to use inside the app, it requires more expertise in APK development to make use of the results. For skilled users, it is a valuable tool. For novice users, it is more of a fun tool to play around with.