• by Mark Walsh  @markfwal, January 8, 2010

With AT&T announcing plans this week to launch five Android phones in 2010, the epic mobile contest shaping up between Google and Apple is sure to intensify.

Things heated up on Tuesday when the feverishly anticipated launch of Google's Nexus One phone was initially upstaged by the news that Apple was acquiring mobile ad network Quattro Wireless for $275 million. The deal follows Google's recent move to buy rival ad network AdMob for $750 million.

Now Android is expanding its rapidly growing domain to include its exclusive wireless partner, AT&T. With its special arrangement with Apple for the iPhone rumored to expire in June, the No. 2 U.S. wireless carrier likely wants to hedge its bets by jumping on the Android express as well as adding a pair of new Palm smartphones with the manufacturer's webOS.

The embrace of Android may especially rankle Apple, since AT&T had been the only major U.S. carrier left not to offer handsets powered by the Google operating system. A comScore study last month found that 17% of prospective smartphone buyers are considering getting an Android phone in the next three months-almost as large a share as the 20% planning to purchase an iPhone.

AT&T also announced an "apps for all" initiative that aims to spread applications beyond smartphones to other mobile devices including feature phones and to support the app stores of all major smartphone operating systems. With about 20,000 apps, Google's Android Market is still only about 20% of the App Store's total, but adding AT&T as a carrier could certainly help attract more developers to the platform and expand its offerings.

"Today some AT&T customers can take advantage of more than 100,000 apps - but only if they have the right handset," said AT&T Mobility president and CEO Ralph de la Vega this week, in a statement that made the iPhone sound strangely more like a drawback than the key to its future. To Google, which has generally espoused a more open approach to technology than Apple, that has to be music to its ears.

Android will also power tablet computers like the prototype Motorola unveiled Friday at CES with a 7-inch screen and 32 GB of internal memory. Apple, of course, is widely expected be introducing its own tablet at a press event later this month. Let the games begin.