My iphone 4s has suddenly started showing a message Norton IDSafe Unexpectedly Quit. What's up?

I open my vault on my iphone 4s  then go to use idSafe and as soon as I do it give me an error message that says "Norton IDsafe Unexpectedly Quit" I can't access any of my passwords on my cell phone. Can you help me-because it renders it useless.

Thanks...