My wife has a galaxy s4 on the tmobile network. She does not have a data plan so she likes to keep her data turned off (to conserve battery) and use wifi when necessary. However because she occasionally gets an MMS message data needs to be on for that. Is there a way I can change a setting maybe to 2g only so the battery drain is less but she can still receive the MMS message by keeping her data turned on always. Any suggestions would be appreciated.