The T-Mobile-exclusive Lumia 810
At first glance you may think that these are the same phones just with a name change. But they are not.
While the “guts” and main features are overlapping, the physical design of the 810 is more “blocky” than the Lumia 820. In addition, the sizes of the devices are slightly different as well, with the T-Mobile 810 being a tad larger, but weighing 15 grams less.
Key differences between the Lumia 820 (L) and the T-Mobile Lumia 810 (R)
Finally, talk-time is also rated higher with the Lumia 810 boasting a 10.2 hour span versus the AT&T Lumia 820 at just 7.5 hours (both over 3G). That key difference is because the Lumia 810 has a larger battery (1800 mAh) than the AT&T Lumia 820 (1650 mAh).
Though subtle, the Lumia 820 (L) is different than the 810 (R)
Hopefully we’ll have more on the subtle design differences soon. But as far as we can see, Nokia is able to make minute adjustments their phone designs for carriers, giving each an “exclusive” device while not compromising in terms of appearance or features.
We predicted this to be the case in our earlier editorial where we speculate about Verizon's Lumia 822.