I hope you know, that whatever phone will have much more energetic value on your body, than all antennas. So when you really think, that you want to lower your exposure, try to wear the phone away from the body. Have it in a Backpack. That increases the distance already much. But I would also emphasize, that there is not yet proofen, that those radio signals have significant influence on our health. So just do it for your beliefs. Not for any real threat 😉