Google bought Android back in 2005 for an undisclosed sum (estimated to be around $50 million). Now, five years later, Google's vice president of corporate development, David Lawee, told attendees at the Stanford Accel Symposium this week that the acquisition was the company's "best deal ever," according to VentureBeat. Most of Google's acquisitions haven't been anywhere nearly as successful, so we're not too surprised Android got first place.

Andy Rubin, Android's co-founder and now vice president of engineering at Google responsible for the open-source mobile operating system, and his team took roughly three years to get a shipping product with the T-Mobile G1's launch in October 2008. Android now accounts for some of the $1 billion in mobile ad revenue at Google. Furthermore, it has already passed iPhone's market share, despite shipping later.

Lawee admitted he had some initial skepticism about the deal. "I saw this guy in my building for two years, walking his dog, and I was like, I hope this guy does something." The fact that Rubin actually stayed after the acquisition was a good thing. "It's obvious when the deal doesn't work out, because the people leave," said Lawee. "That's the key metric: Is the technology being used? A lot of it depends on the perseverance of the team coming in."