We used to lean on our memory to get around, find places, and arrive on time. This didn't work too well, so some of us carried fold out maps. No one uses printed maps anymore, at least no one with an iPhone. A maps app is core to our mobile lives. Sure, iPhone owners complained mightily that Apple Maps isn't nearly as good as Google Maps. But the uproar just goes to show how much we rely on a maps app these days.