Think your smartphone is clever? Search giant Google has plans to make that little camera on the back of mobile devices not just for selfies, but part of a personal, real-time 3D mapping system that makes 250,000 measurements per second. Although it's only in the prototype stage, Google is set to launch new Android phones this year that boast a "human-like understanding of space and motion". So, what's it for? Google's Project Tango - straight out of the company's Advanced Technology and Projects (ATAP) division - is about doing much more with your environment. At its most basic, it's about never getting lost. Unlike Google Maps or any kind of GPS system, which rely on exterior hardware and infrastructure, such as satellites, cameras and databases stuffed with images and maps, Project Tango is about making the phone so intelligent that it continually tracks its own full 3D motion, simultaneously creating and recording a map of the environment it's being used in. Project Tango is no app. It requires new sensor-packed hardware capable of more than a quarter of a million 3D calculations per second as it constantly updates its position and orientation. "Project Tango strives to give mobile devices a human-like understanding of space and motion through advanced sensor fusion and computer vision, enabling new and enhanced types of user experiences, including 3D scanning, indoor navigation and immersive gaming," says Johnny Chung Lee, technical program lead of the ATAP group. One of Google's tech partners is Siegen, Germany-based PMD Technologies, which has developed a tiny 3D camera module for smartphones. "We strongly believe that the future of 3D applications is mobile," says Jochen Penne, director of business development at PMD. "As 3D sensors start showing up in phones and tablets, those technologies will enable millions of people to capture, share and interact with the world around them in real 3D." The uses of Tango are only now becoming clear. A Tango phone can capture the exact dimensions of your home; that could be useful if you're out shopping for a new sofa, but it's likely a must for architects, builders and estate agents. As well as taking you to a street address, a Tango phone could tell you when to step out of the lift, let you retrace your steps around an unfamiliar office, or find a product on a shelf in a store. It could also help visually impaired people navigate. Google also suggests some gaming scenarios that could make virtual reality the real deal; why not make your home the battleground in a shoot-em-up, or play hide-and-seek in your house with your favourite game character? That last scenario - the device-sanctioned imaginary friend - will worry some parents. Google isn't the only internet giant to be working on 3D sensing and motion tracking by mobile devices. Facebook thinks virtual reality is best done on a headset, as proven by its purchase and continual talking-up of Oculas Rift, a "major new computing platform" (according to Mark Zuckerberg, CEO of Facebook), which has sold more than 100,000 units. It's thought that Oculas Rift could create a "social space" where virtual representations of Facebook users can meet each other. However, Zuckerberg thinks it could take a decade before a big enough ecosystem builds up around Oculas Rift for it to become significant; the goal is 50 to 100 million sales. Project Tango is destined to arrive much sooner. On what device we will first see the fruits of this research are unclear, with Google's prototypes so far including both a smartphone (with three cameras) and a seven-inch tablet, although we do know that it will be in 2015 - and probably via a tie-up with LG. Either way, the landscape will soon become a lot clearer.