How does Messaging (ie. text messages) work? Does the message go over a wifi connection or does it have to be via LTE or 4G Data or whatever? I am trying to send messages to a friend in Regina (I am in Richmond, BC at the moment) and she says she's getting blank messages. I've checked a few of the ones I have sent and the phone says that they were sent. The thing is that this is not a constant thing...sometimes she gets them but more often not. Is there a setting I need to enable? I've done text messaging to others not in my area code and haven't had any reports of blank messages to them. The phone is a Galaxy S4.