According to an update at the USPTO (US Patent and Trademark Office), Google acquired 188 granted patents and 29 pending patents from the granddaddy of things that go beep, IBM, on Dec. 31, 2011. This is just three months after Google purchased over 1,000 patents from Big Blue back in September. Not all these patents are for their mobile division (Google still does this little thing called search), but their are more than a few that cover things your Android phone or tablet (as well as other platforms) can do like web page rendering and VoIP. We'll let interested parties check out the source link for a more detailed list.
No financial details have been provided, but we imagine it is far cheaper than lawyer and court fees for the upcoming patent meltdown that's sure to hit had they not purchased the patents outright. Google seems to be preparing for the day when it all hits the fan as well as licensing and purchasing new technology to make their offerings a bit better.
Source: SEO by the Sea