Android this week: Transformer Prime; Galaxy Tab 7.7; Kindle Fire still hot

This week, two of the latest Android(s goog) tablets arrived on my doorstep: An Asus Transformer Prime and a Samsung Galaxy Tab 7.7. Both are upgrades over models from last year and even though I’ve only spent a little time with each, both have already impressed me for various reasons.
The Transformer Prime is unique in that it supports an optional $150 keyboard dock. Besides adding easier input with a full keyboard and trackpad, the dock adds another 8 hours of battery life to the 10-inch tablet, which can already run for up to 12 hours on its own. The dock also adds a full-sized USB port, which has let me use an Xbox 360 controller to play PC-quality games. Here’s what it looks like:
Two other Transformer Prime standouts are the processor and software. This slate is powered by Nvidia’s (s nvda) Tegra 3 chip; a quad-core processor with 12 graphic cores, which helps explain the excellent gaming. The chip is also powering Android 4.0, or the Ice Cream Sandwich version of Android, which is improved slightly over Honeycomb, which ran on tablets last year.
The Samsung Galaxy Tab 7.7 isn’t yet available in the U.S. — an LTE version is coming for Verizon(s vz) — but I purchased a unit from an importer. I’ve used the original Galaxy Tab daily since December of 2010 and the newest Samsung slate is already proving to be a solid upgrade.
The 7.7-inch display and 7.89mm thickness keeps the device portable for most situations and uses Samsung’s Super AMOLED Plus technology with 1280 x 800 resolution, making for superb visuals and viewing angles.

Unlike the Prime, this tablet uses a 1.4 GHz dual core chip, but I’m already finding it to more than powerful enough for most tasks. The Galaxy Tab 7.7 also runs on Honeycomb, so owners will have to wait for an upgrade to Android 4.0. Since the unit only just arrived, I’ll have more thoughts to follow this week.
Although these two tablets are new, the most popular Android slate appears to be one that doesn’t use Google’s services at all: The Amazon Kindle Fire may be the best selling Android tablet yet. Android tablet sales spiked to an estimated 39 percent of the tablet market last quarter, but by some measures, the Kindle Fire accounts for 40 percent of all Android tablets sold during that time frame. That shouldn’t surprise, given the relatively low $199 price tag and the functionality gained for that cost.
On the software side of things, my favorite third-party Android browser gained some new tricks this week. Dolphin Browser, which supports themes and extensions, added support for both Skitch and Evernote; two popular and useful services. Skitch allows you to draw or annotate on-screen while Evernote is a powerful cross-platform web-clipping and note-taking application. Both the browser and these new supported services are free on Android.