OS X Yosemite: The Missing Manual

Maps

When Apple brought its own Maps app to the iPhone in 2012, the underlying databases had a lot of problems. They didn’t include nearly as many points of interest (buildings, stores, landmarks) as Google. Addresses were sometimes wrong. Satellite view showed bridges and roads melting into the sea. In a remarkable apology letter, CEO Tim Cook recommended using one of Maps’ rivals.

But some of Maps’ features are pretty great—and now that Maps is a Mac app, too (Figure 11-18), there’s some handy synergy with the iPhone or iPad. You can look up an address on the Mac and then wirelessly shoot it over to the phone for navigation in the car, for example. Or simply walk over to your Mac; thanks to Handoff (Handoff), whatever map was on your phone is now on your Mac. And Maps’ smarts are wired into other OS X programs, like Calendar, Contacts, and Safari.

UP TO SPEED: How the Mac Does GPS

When you first open Maps, your current location appears as a blue dot on the map. Now, the Mac doesn’t have GPS; how does it do that?

It uses a sneaky trick. Metropolitan areas today are blanketed by overlapping WiFi signals. At a typical Manhattan intersection, you might be in range of 20 base stations. Each one broadcasts its own name and unique network address (its MAC address—nothing to do with Mac computers) once every second. Although you’d need to be within 150 feet or so to actually get onto the Internet, a laptop or phone can detect this beacon signal from up to 1,500 feet away.

Imagine if you could ...