You have been using FlickStackr/PhotoStackr without problems, suddenly when you try to launch it, it won't start it just crashes after a few seconds.
There could be something corrupted in the cache, try cleaning the cache
- Stop FlickStackr/PhotoStackr: Double press the home button on your iPad. The running apps will appear at the bottom. If you can see the FlickStackr/PhotoStackr icon, tap and hold on it until a red circle appears, this will stop FlickStackr/PhotoStackr.
- Launch the Settings app and scroll down until you see the listing of apps, tap on FlickStackr/PhotoStackr.
- Tap on Cache
- Set Clear Cache to "ON", and go back tap on the FlickStackr/PhotoStackr arrow at the top.
- Now launch FlickStackr/PhotoStackr.