Google has bought Motorola Mobility, the phone and tablet arm of the electronics giant, for $12.5 billion in a move it says will "supercharge" Android.

The deal is massive because it means that Google is now in a position to push on with its own branded devices, rather than piggybacking on other companies' work as it has in the pas with the Nexus One (HTC) and the Nexus S (Samsung). It has stated that Motorola will continue as its own brand - although how long that will last remains to be seen.

And Google is also boasting how the acquisition will strengthen its patent position in the face of competition from rivals like Microsoft and Apple.

"We recently explained how companies including Microsoft and Apple are banding together in anti-competitive patent attacks on Android," said Larry Page, co-founder and CEO of Google.

"The U.S. Department of Justice had to intervene in the results of one recent patent auction to 'protect competition and innovation in the open source software community' and it is currently looking into the results of the Nortel auction.

"Our acquisition of Motorola will increase competition by strengthening Google’s patent portfolio, which will enable us to better protect Android from anti-competitive threats from Microsoft, Apple and other companies."

Google is also promising to keep Android available to Motorola's rivals. "Android will remain open," said Page. "We will run Motorola as a separate business. Many hardware partners have contributed to Android’s success and we look forward to continuing to work with all of them to deliver outstanding user experiences."

Again though - for how long? Eyebrows from Android's key players are bound to be raised. Surely Motorola will get first dibs at anything Android related - as it did with Honeycomb on the Xoom.

The deal is still subject to US regulatory approval though - which may cause a few problems as the Android division is already being probed by anti-trust investigators. However, the companies said they expect the takeover to be completed in late 2011 or early 2012.