Important: PLEASE READ THIS ENTIRE DESCRIPTION BEFORE PURCHASING!UNLOCK KEY (License) for the Aldiko Sync application to enable extra features.This app unlocks the "Pro" features of the Aldiko Sync application. You must have the latest version of the Aldiko Sync (free) application installed on your device.This app will NOT show in your app drawer and CANNOT be started. IT ONLY NEEDS TO BE INSTALLED ON THE DEVICE TO UNLOCK EXTRA FEATURES.To verify correct installation, open Aldiko Sync after installation of this app has completed and the title should read "Aldiko Sync Pro".** Before complaining about the sync frequency in the Pro version, please read the entry about it in the FAQ here: http://forum.xda-developers.com/showthread.php?t=1253576 **Thanks!