Facebook acquired fitness and health tracking app Moves, that keeps track of daily fitness routines and automatically determines a user's physical activity. Facebook will buy ProtoGeo Oy, maker of the mobile app. The app works quietly in background constantly gathering data from the phone's accelerometer, displaying the activity in a well-designed interface. Facebook did not disclose the price it is paying for the app, but said it was nowhere i comparison to its recent acquisitions. "The Moves team has built an incredible tool for the millions of people who want to better understand their daily fitness activity, and we're looking forward to the app continuing to gain momentum," said Facebook. According to ProtoGeo, the app, available to both Android and iOS users, has been downloaded over four million times and has millions of users. The app was called a "Surprise Hit" by Apple's iTunes Store. "For those of you that use the Moves app -- the Moves experience will continue to operate as a standalone app, and there are no plans to change that or commingle data with Facebook," said the Moves team in a blog post. Facebook released a statement saying the acquisition was part of the company's multi-app strategy and would become apart of Facebook's suite of applications. Key members of the Moves team are expected to join the Facebook team in Menlo Park, but the app will continue to function as a standalone unit.