[JeffKay]

I was getting this consistently because of the gps. Whenever an app tried to access the gps, reboot. I read this on the net.. it fixed it so far.

Step1, Call sprint and get your msl code(unlock code)
Step 2, launch phone dialer and press "##GPSCLRX#"
Step 3, input code sprint hopefuly gave you (phone will reboot in 20 seconds)

That fixed it for me.