When I visit museums I usually use a mapping app to get there, and then I’m immediately lost once I’m inside. That changed tonight, thanks to Google. At Mobile World Congress, Google and Lenovo are demonstrating a useful feature of Project Tango: indoor navigation. Google has been experimenting with tablets that map the world around them, and I got to try out navigating a museum with one.

While it was a controlled experiment inside a small section of Barcelona’s national art museum, it felt a lot more real than some of Google’s previous demonstrations of the Project Tango tech. We’ve tried Project Tango before inside Google’s own headquarters (mostly for gaming), but today’s museum tour offered a practical reason for why you might be interested in owning a Project Tango-enabled phone in the future.

The tour was brief, but I was able to navigate between important paintings in the museum with ease by following a live dotted line projected onto the camera view. Google’s interface for Project Tango indoor navigation looks very similar to Google Maps, allowing you to tap to navigate to points of interest inside buildings. Using the live view felt just like augmented reality demos we’ve seen time and time again, but the difference here was the accuracy. I could spin around and try to confuse the demo, but it kept on pace each and every time.

While the bulk of Project Tango uses sensors and cameras in the device to map the 3D space of a room, Google is also using augmented reality to point out features inside buildings. In the museum demo I could hover over paintings and find out more information about even the smallest detail on the canvas. It felt relatively useful in a museum context, but the fact I was navigating an indoor building was a lot more impressive.

Lenovo is launching the first Project Tango phone this summer

Google appears to be pressing ahead with Project Tango, too. Lenovo and Google have partnered up to launch the first Project Tango smartphone this summer, but they weren’t ready to show this off today. Instead, we used the same Project Tango development kit (tablet) to navigate around. The phone itself will be "less than 6.5 inches" in size, with the camera array built directly into the back of the device.

Once Project Tango truly comes to life then Google will face a big challenge of getting other device makers to integrate the technology, and convincing museums or retail stores to start mapping their environments. Most of Project Tango will be crowdsourced data, just like Waze collects traffic data. It’s still early days for Project Tango, despite Google experimenting with it for a couple of years now. Indoor navigation is still very much a dream and a big challenge, but if more smartphone makers get behind Google’s vision then we might all finally be navigating around indoors soon.