I have been playing this game ever since launch. Now, when i try to open the app, after a few seconds, it crashes.

Any way to fix? I am on iPad 4 on iOS 8.3.

The first suggestion is to fully power off your device. This should allow you to access your Vault again. If you would report the conditions surrounding this in the unofficial bug thread.

http://www.gamesas.com/topic/1522042-the-unofficial-game-bug-glitch-or-crash-report-thread/


I will take a guess that you had several children "pop" at the same time. Multiple baby births tend to be one of the areas that can cause even "supported" systems to have issues. Especially with an already large and highly populated vault.