T-Mobile Galaxy Tab 7 plus Munching ICS but Only from Kies
Android Central

T-Mobile Galaxy Tab 7 plus tablets are graduating from its built-in Android Gingerbread software, now moving up to the newer Ice Cream Sandwich. But the Android 4.0.5 ICS update is not available over-the-air and is currently "optional". The software update can only be downloaded at Samsung software manager called Kies. The update to the latest Android OS, Jelly Bean, is expected to be available in the fourth quarter.

What Else You Need To Know:

- Only users with the latest Kies and at least a 50% charge can download the new software.

- ICS updates for the Wi-Fi only models were made available earlier this month.

Other sources

Honeycomb to Ice Cream Sandwich is more than an optional update if you ask us. It’s mandatory! The performance enhancements alone are worth the change, not to mention it will help all apps run better on your Android tablet. - Cory Gunther, Android Community  
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