I'm having a bizzare problem that has been occurring for months.. I have a jailbroken iPad 3 running iOS 6.1.2. For some reason no app that is related to pdf files will open. And they used to work fine, even with jailbroken. No updates have occurred except app updates.. (these are paid professional versions). PDF Expert won't open (splash pages comes up for about 10 seconds then crashes) PDF reader won't open (splash pages comes up for about 10 seconds then crashes) Good Reader won't open (splash pages comes up for about 1 second then crashes) Quick Office does open. All other apps work fine. I have tried hard reset. I have tried uninstalling and reinstalling (including deleting from itunes and downloading fresh copy) I have tried Safe Mode to deactivate all tweaks (which I don't really have many at all). I have tried uninstalling all tweaks. I've tried deleted data from cloud storage It only occurs with these apps which all seem to be pdf viewers. Any thoughts.