It’s not that they “don’t support” phones, it’s just that they can pick and choose who they decide to sign service contracts with. They lease the bandwidth from he FCC and in doing so have the right to use it as they see fit.
I’m not sure what AT&Ts motive for being vehemently opposed to unlocked phones is but it’s well documented. Theoretically any new user, be that a new contract iPhone buyer, a used iPhone buyer with a month-to-month contract or a unlocked GSM phone buyer with a pay as you go contract is all extra coin in AT&T’s pcokets. But, for whatever reason AT&T has decided that those folks with unlocked phones are undesirable. I theorize that it just their fear of a slippery slope of manufacturers making real unlocked phones at cheap prices undermining their hold on consumers with binding contracts and forcing them to actually compete in a free open market, but that’s neither here or there.
So, Google claimed it was going to make an unlocked Nexus One for the masses. For whatever reason they hoodwinked everyone on that promise by making a phone that was technically “unlocked” but wasn’t actually available for use on all frequencies.
The only differences between the frequencies supported by the Nexus One and iPhone are the UTMS bands, iPhone on 1/2/5 (2100/1900/850 MHz) and Nexus on 1/4/8 (2100/1700/900 MHz). Presumably it’d be trivial to add support for the other bands, and I’m not sure which carriers operate on which bands. There are likely issues when roaming internationally that could cause conflicts which motivated Google to choose the frequencies they did.
So, supposing that Google had to make several choices in which frequencies to support and which technologies to support taking into consideration carriers on many continents with different allocated bandwidths you have to step back and decide which carriers are liable to be the highest priority.
AT&T and Apple who are enemies and might not play ball, or T-Mobile and the European/Asian GSM carriers who have big markets and want to play ball. AT&T getting left out in the cold with it’s professed disdain for unlocked phones and Apple and Google’s open war makes sense.
Now, there are probably lots of technical details that could supersede business and politics and I don’t pretend to understand them all, but there’s essentially no doubt that Google could have made this phone for AT&T. Since AT&T is in bed with their enemy they chose not to.
The issue is why Google decided to use language to let people believe otherwise.
GSM 850 900 1800 1900