Regardless of the fact that AT&T acquired T-Mobile USA and the latter has confirmed it will not be offering the iPhone, yet, a report claims that T-Mobile USA is now home to about 1 million unlocked iPhones in the USA.iPhone 4.
Also, iPhone 4 owners won't be able to capitalize on the 3G or 4G data speeds offered by T-Mobile as difference in radio frequencies of AT&T and T-Mobile exist. So if someone bought an iPhone from AT&T on contract but unlocked it to use T-Mobile, they won't be able to get high data speeds. On the other hand, Apple has now begun to sell officially unlocked GSM iPhone 4 at Apple Retail Stores in the US.
When the T-Mobile USA spokesman was asked whether or not the company intends to officially release micro-SIMs, it was said that they are under production. When asked about a possible T-Mobile iPhone release, no comments were made.