SAN FRANCISCO -- The popular navigation app Waze is putting a new twist on the phrase "tunnel vision." It's trying to ensure drivers relying on digital maps don't lose their way when their GPS signal disappears in tunnels.

Waze plans to keep drivers connected in those GPS-less situations by installing beacons that will transmit to smartphones and tablets in the tunnels that the company has it its database, covering about 7,500 miles (12,000 kilometres) around the world. The beacons can maintain map connections, as long as the drivers turn on their Bluetooth signal.

The beacons will begin working Wednesday in two Pittsburgh tunnels, Fort Pitt and Liberty, and another in Israel, where Waze was founded before Google bought it in 2013.