AT&T is planning to update four Windows Phone 7 smartphones to the Mango release starting as early as Tuesday, according to internal AT&T emails received by a Web site.
Three phones are getting Mango, which Microsoft also calls Windows Phone 7.5, the HTC Surround, LG Quantum and Samsung Focus, according to email documents received by WPCentral.com .
The documents also say that the fourth phone, the HTC HD7S, will get the update in early to mid-October. To get the update, customers will need to download new Zune player software and plug in their phones for power.
For the Samsung Focus, there are two update periods: Sept. 27 for the 1.3 hardware revision and Oct. 31 for revision 1.4.
The email documents did not discuss timing for AT&T's fifth Windows Phone 7 smartphone , the Dell Venue Pro. Some expect Dell to handle that update separately.
An AT&T spokesman would not comment on the email documents and said AT&T has not officially announced specific dates for the updates. "We ... will provide more information on our Facebook page as the time draws near," the spokesman said via email.
The spokesman also said customers that own the phones affected will receive notices of updates when they are ready, with the updates occurring "on a rolling schedule with different phones being updated at different times."
Mango will have 500 new features, according to Microsoft , including the Internet Explorer 9 browser . Microsoft blogged about developer capabilities with the browser update in Mango on Thursday.
AT&T said on Sept. 12 that it would update its four current Windows Phone 7 phones to Mango, without giving dates. The carrier also said it will launch three new Windows Phone 7.5 phones this fall -- the HTC Titan, Samsung Focus S and Samsung Focus Flash. All the new phones will run on AT&T's fast HSPA+ 4G network.
Some bloggers are speculating that AT&T will release the new Mango phones about the same time as it update the existing Windows Phone 7 devices.
Matt Hamblen covers mobile and wireless, smartphones and other handhelds, and wireless networking for Computerworld. Follow Matt on Twitter at @matthamblen or subscribe to Matt's RSS feed . His e-mail address is mhamblen@computerworld.com .
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