I'd suggest a full restore as new (without any iCloud or iTunes backups) and load all of your apps manually from the App Store purchased section - following this proven process had lead to resolution of many crashes.Even after upgrading to iOS 7.1b4 I am still getting a lot of application crashes especially from Safari. All the crash logs show "low memory" errors so either memory management in iOS 7 is horrible, Safari has a severe memory leak or garbage collection bug, or the iPad Air does not have enough memory for basic operations such as web browsing with a few open tabs.
I follow this process for every build on each of my iPhones and iPads and have only had two crashes on 7.1 beta 2 and later.
iOSBry