MOUNTAIN VIEW, Calif. - Google is buying cell phone maker Motorola Mobility for $12.5 billion in cash in what is by far the company's biggest acquisition to date.

Google Inc. will pay $40.00 per share, a 63 percent premium to Motorola's closing price on Friday.

The companies say the deal has been approved by the boards of both.

Google CEO Larry Page says that the deal with "supercharge the entire Android ecosystem."

The deal gives Google direct control over the maker of many of its Android phones.

In premarket trading, shares of Motorola Mobility Holdings Inc. are up 60 percent, or $14.72, to $39.19.