Requirements: An archive manager (such as WinZap,Power Archive) that is capable of extracting and making .rar archives.
How to unpack .apk files:
1. Open Formatter
2.Click the “Choose File” button and choose your apk file. Enter “.rar” (without quotes) in the first box. After that, your desired name for your .rar archive and click the big “Rename!” button
3. Go to the folder where your .apk file was. You should see a .rar archive, named by the name you entered in Formatter. Extract it with your archive manager.
How to repack .apk files:
1. Compress the extracted files in a .rar archive
2. Open Formatter
3. Choose the .rar archive you made a minute ago
4. Set the format to .apk
5. Set the name to whatever you want
6. Click the big “Rename!” button