My Droid X keeps restarting on me at random. At first this made me go well every phone has it's quirks now it's just ticking me off. It's happened while I've been on the phone and while it's just sitting idle. If anyone has anything helpful please comment!
I usually dont suggest this but it sounds like you got a conflicting app, I would backup, hard reset and then install app slowly and see if you can identify the conflicting app.
Common problem....check out the motorola support forum on this issue:
https://supportforums.motorola.com/thread/33153?tstart=0 Once there, be sure to register and add your phone to the list. Good luck. FYI - I am on phone #3 with the same reboot issue (#1 and #3 reboots on its own - -phone #2 arrived with a bad handset earpiece.