Google has acquired BumpTop, which enables 3D multitouch desktop on Windows and Mac computers, the company confirmed.
BumpTop uses "pile creation techniques" to shuffle and stack documents as if they were cards in a deck.
The app was originally created for use with a pen-style stylus; the startup added multitouch last September, looking to capitalize on the shift toward touch-screen interfaces by letting users move, zoom in and out on, and access documents with their fingers.
Multitouch has been popularized by Apple's iPhone and iPad and Google Android smartphones. BumpTop CEO Anand Agarawala in this video dryly shows how users can crop photos and upload the pictures to Facebook.
It is easy to see how such technology would appeal to Google, which is reportedly building a tablet computer based on Android to rival the iPad.
Wellington Financial noted the acquisition May 1 after finding this blog post from the company.
A Google spokesperson also confirmed the purchase for eWEEK May 2 but would say only: "We're happy to welcome the BumpTop team to Google, but we don't have any specific information to share."
BumpTop is just the latest in a string of small purchases, each one seemingly more obscure than the last. Google ignited its shopping spree last August when it bid for video codec provider On2 Technologies.
Other buys include display ad provider Teracent; real-time collaboration app maker AppJet; social search engine Aardvark; mobile mail app maker ReMail; collaboration software maker DocVerse; Web photo editor PicNik; video platform maker Episodic; visual search provider Plink; and chip maker Agnilux.
Google just nabbed game widget maker LabPixies April 28.
Google's $750 million blockbuster bid for mobile ad maker AdMob has yet to be approved and may well be struck down by the Federal Trade Commission.