It's now more than a month since I left T-Mobile for AT&T. The overall impression is good. But let me tell the whole story.
My major problem with T-Mobile was its spotty coverage. It worked ok where I live, worked ok when I drove, but it didn't work when I'm at work. People were asking me why you don't have your phone on when we call you. The problem was that the phone had to be placed next to a window when I am at work, and we are in an office area with good outside reception. The phone only worked in a certain corner of my office, when placed on a bookshelf. Even so, when I got a call, I was able to pick it up, but generally it would drop after a few seconds. After that, a new call cannot be placed until nearly 3-5 minutes after the drop, as the line would be blocked completely. Zero bars and no internet.
I first thought it was my phone. So I changed phones several times, used Samsung Galaxy, Nexus 4, iPhone 3GS, some older Samsung flip-phone. Same results. It's great to be on GSM network. I could switch phones by popping in and out the same Sim card. Later I ordered a new Sim card from T-Mobile, but with the same results.
Being a computer programmer, I have a clue how databases work. The whole behaviour of T-Mobile handling my Sim card would be as an old customer I was placed in the very bottom of the Users' table. Perhaps even in some sort of an ArchivedUsers table. I just can't explain the huge lag in the connection other than being on the bottom of the Users list, and the database index not being updated properly.
Another interesting problem with T-Mobile, which is probably only interesting to technical types, is that it was dropping my Internet connection every 2-3 days. As I was hitting a certain data allocation at a time. After a day or two of Internet use with my Nexus 4, most of which was e-mail and occasional use of Google Maps, the phone would stop obtaining the IP address completely. The only cure was to shut down and reboot. (Think Android issues? nah! read through..)
But despite the lags and poor connection, I was willing to stay with T-Mobile until the end of days. Mostly because they are inexpensive, and my contract was long gone. Nothing beats T-Mobile prices with the service they have. They are good.
The last drop happened when my daughter started attending college. Needless to say, we asked her if she wanted a new phone. She said no, as she wanted to save money. I respect that. The problem however showed up where it was less expected. Guess what, the T-Mobile reception in her area was next to nothing. So.. we started shopping for a new phone, a new calling plan, and ended up with AT&T.
As part of the new plan with AT&T, they sent us two brand new iPhone 5s's. I've never owned an iPhone before. (A used 3GS for testing our app don't count.) We've always been Android people, sort of a geeky type.
After two weeks of everyday use of iPhone 5s, I ordered myself a nano-to-micro sim card adapter. I could barely wait until it arrived so I could go back to my Nexus 4. You may ask why.
Is the iPhone bad? Oh, not at all. Very light, slick looking device, all nicely machined from an aluminum cast. Fast? yes. Reception? good.
So, what was the problem?
The short answer would be that the Nexus 4 is better. It's a bit wider, yes, but the wider screen is so much better, I won't even compare them. The 150 pixels make so much difference. That's not all though. Most of the advantages come from Android niceties. The totally awesome Back button, Multitasking, and clever use of the Multicolor LED indicator. Here is an example.
With iPhone, if an email arrives when you are not around, or you didn't hear the beep, you won't know until you pick the phone up and look at the screen. With Nexus, the LED indicator on the front panel, the same place where iPhone has its main button, starts slowly blinking with one of the 4 colors. I assigned various colors to different email accounts, and could instantly spot an important message.
Another cool thing is having a Google Talk or any other background app run and notify you when someone is calling you, without having it on the front page all the time. It may drain the battery a bit more, but Nexus never gave me any battery problems. It's fairly good with battery even after a year. I rarely had less than 1.5 days on one battery charge with my normal use (4-6 hours of book reading, dozens of emails and a few calls a day). I don't watch movies and I don't play war games on the phone.
Now, back to the AT&T service. The reception is great so far. I mean, it's just awesome. It works everywhere. I'm back to my Nexus with the AT&T SIM card in it, and I finally feel like I am actually using a real phone, and not a dumb pager with diode-like reception. So far, no IP address drops after 3 days, not even after a week of use. (Hey network engineers, any thoughts?)
By the way, a nano-sim card adapter made my transition from iPhone 5s to Nexus completely easy. I rebooted my new Android phone, and it picked up the AT&T network right away, including HSPA internet service. I'm a happy camper so far.