All apps crashing on both iphone and ipad

Hi,

For about the last 2-3 weeks I have been experiencing an issue where all apps are crashing on my ipad 2 - initially I thought it may be a hardware problem, but the problem after a few days started to occur on my iphone 4 as well. So methinks it can't be a hardware problem.

Both ipad and iphone are running the latest version of ios 6.1.3 - I have reset the ipad and restored a backup, but still occurring.

I am either thinking it is an app running on both the ipad and iphone that is causing the problem (though I did uninstall any recently installed apps) or a problem with iCloud and the syncing of devices.

Typical behaviour - midway through typing a text message app crashes, if I don't kill off in task manager app will crash straightaway or within 20 secs of relaunching, if I do kill off the app I may be lucky and get 5 mins before it crashes - screen goes black briefly before going back to home screen. Text I am midway through typing is gone when I go back into Messages.

The above happens in pretty much all apps - games, safari, spotify, fliboard - though hasn't cut out any phone calls.

Has anyone experienced anything similar and if so how did you resolve?

Thanks,

Simon