I too use Green Power app in my Android device, but it has never shown such problem. It's working fine in my device.
It may have occurred after you have updated the software. You can try to get the latest version of the app from Google Play.
Book Keeper app for Android is a perfect app for maintaining such records. You can download this app from...
Alarm Clock Plus and AlarmDroid are also very similar apps that you need.
I haven't seen such an app for Android till date, but it is really a good idea if possible. I really appreciate it Zabrak999.