Can anyone say whether upgrading from the 11 to the 13 will make a difference in signal strength? I often only have1 bar on my 11 at home and people who call me say there's a recording saying that there's no reception. When I'm out and about, I get 2 bars LTE. Never had this problem until we moved . T-Mobile (my provider) switched out my Sim card et voila - I had 4G and 4 bars...in their store. Ha. Get home and I'm back to the same weak signal. I've tried all the usual suspects (on/off, airplane mode, etc). Will switching providers make any difference? Thanks.