T-Mobile has a hit on its hands with its Android-powered smartphone, as the T-Mobile G1 has sold more than a million units in about six months.

The news came during Deutsche Telecom's earning call, and it's a good sign for the Google-backed operating system. The G1 launched in October, but it was unclear how well it would be received because it was an untested OS and lacked the enterprise features that generally attract smartphone buyers.

The handset has a 3.2-inch touch screen that slides up to reveal a full QWERTY keyboard. It also has the features one expects from a high-end smartphone, including Wi-Fi, Bluetooth, and GPS. One key differentiator of the G1 is that it has deep integration with Google's Web services, including Gmail, Google Maps, and Google Calendar.

The G1 has been the recipient of T-Mobile's largest ad campaign for a phone, and it also has the benefit of being one of the first handsets capable of utilizing T-Mobile's 3G network. Rivals like AT&T, Sprint Nextel, and Verizon Wireless have a large lead in 3G deployment, but the fourth-largest U.S. carrier is quickly rolling out its mobile broadband network.

Companies like Samsung, Motorola, and Sony Ericsson are considering bringing Android-powered smartphones to the market, and the sales success of the G1 could spur other manufacturers to take a closer look at the Google-backed mobile operating system.

While the G1 has been successful, it has not been as popular as some of it smartphone rivals. Verizon's BlackBerry Storm launched with multiple software bugs that led to mixed reviews, but it sold 1 million units in about three months. Apple's iPhone 3G sold 1 million units worldwide in its launch weekend and likely took about a month to sell 1 million units in the United States.

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