Ever since I upgraded to 7.1.1 I keep finding my Cellular data turned off.
I turn it on, go out do my thing, come home or go to the office, go to listen to SatelliteGuys Radio in the car and get a message that my Cellular data is turned off.
I don't know why it's doing this... Maybe its part of the battery saving? (When I am on WIFI for awhile maybe it turns off the Cell Data?)