I just switched to Verizon...Here's why.
I was issued an iPhone 4 by my company over a year ago. The corporate service provider is AT&T.
My home is in the center of Berkeley, CA (population ~100,000). If you don't know, Berkeley is across the bay from San Francisco. There is a BART (light-rail train) station about eight blocks from my home.
In my home, I typically have no signal. I gave up on using the iPhone to make calls, and installed the Skype app so that I could make calls over my home wi-fi. I frequently miss incoming calls because of the poor-to-non-existant signal.
Walking from my house to the BART station takes about 10 minutes. I can make calls for about half of that walk, but the data connection is so poor that I can barely perform a single Google search in that time. Just outside the station itself, I can sometimes not make a call because the signal drops to one bar.
Riding the train in to San Francisco affords only about five minutes of usable data service time for a 30-40 minute ride. This connectivity has actually been decreasing noticeably over the past few months. It used to be that any time I was out of the underground sections of the rail, I had data connectivity. Lately, the signal is non-exisstant execpt for two very small windows of coverage just before going back underground.
Now, for some reason I was able to put up with this, mostly because my company was paying for the service, not me. But when I wanted to get an iPhone for my wife, I wound up getting it for her through AT&T. Silly me.
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