New Go Locker Theme Kit Kat Lockscreen HD! Go launcher ex locker. Turn your phone into a Kit Kat Phone. This is not an operating system. It's a unlocker. You must have GO LOCKER app Installed to use. Features: 1. Cool Locker Screen that makes your phone outstanding; 2. Support customise wallpaper; 3. Security locker; 4. Alarm. How to use: 1. Make sure GO Locker EX v1.