Mike,
A rare / random lock up is not impossible, but this should be a rare occurance. A reboot should always clear the problem. If you had two lock-ups in back to back short sessions this might indicate a problem. We had an a few months ago with the low-enroute charts causing a memory leak that would eventually lead to a lock up, if you have an old set of charts and you were panning around in this mode, this could explain it. Otherwise if you see this again I suggest you contact our support department for a diagnosis.
Also, I'm moving this thread to the iFly Owners forum.
Thanks,
Walter