Enemy number one of GPS and navigation apps might be tunnels. When you're driving through what's basically a deep cave, your location isn't always accurate until you get to the other side—we still haven't found a way to make those pesky radio waves bend the laws of physics. Google, however, might have just come up with the perfect way to keep navigation alive inside tunnels, and it's coming to a Google Maps app near you.
Google Maps has rolled out the ability to maintain Maps connectivity in tunnels. How, exactly? By using Bluetooth beacons. This option, which is disabled by default, allows Android phones to connect to beacons installed inside major city tunnels, ensuring users receive crucial information like in-tunnel exits and accident alerts. The feature has already been available in Waze for some time, and the company is now taking the step to launch it on Maps as well. It's not clear why it wasn't available on both apps given that this is not a "new" feature, but it's available now.
As we mentioned, this feature relies on Bluetooth beacons in tunnels across global cities like New York City, Chicago, Paris, Rio, Brussels, Oslo, Sydney, Boston, and Mexico City. There's a big catch with this, however, and it's the fact that the feature depends on the existence of these Bluetooth beacons, which aren't a thing in a lot of tunnels around the world. If a tunnel you're going through happens to not have Bluetooth beacons, it'll work exactly the same. Information flows unidirectionally, from beacons to smartphones, so they're not a privacy concern. The beacons themselves are basic battery-powered controllers, too, employing low-powered Bluetooth technology.
The feature is exclusive to Google Maps on Android, leaving iPhone users without access (and presumably lost in tunnels), at least for now. To activate Bluetooth beacons for navigation, Android users can navigate to Settings > Navigation, then access the 'Driving Options' section to toggle on the 'Bluetooth tunnel
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