When I was a kid I remember my parents having something called a “Perly’s” in their car. It was basically a map book and it was the best thing around. 

You would start by looking at a big grid of the city and then you’d find the specific area you were looking for and then flip to that page. If you were on the road a lot for work, a Perly’s was a mandatory addition to your car.

Things have obviously come a long way since then. It could take you a long time to find the street you were looking for in a Perly’s. I remember doing that from the passenger seat. Now our phones do that for us and if the connection makes us wait for more than few seconds, we get irritated.

But we’ve also moved beyond just static maps. 

The other morning I was driving out to the suburbs and I saw this road sign telling me that – given current traffic conditions – it was going to take me 15 minutes to get to HWY 427. 

Have you ever wondered how they come up with those time estimates?

There are a few ways to do it. But here in Toronto along the Gardiner Expressway and Lake Shore Boulevard it’s done using your mobile phone. Phones have unique network identifiers called MAC addresses. And when they try and connect via Bluetooth or Wifi they actually send out their MAC address.

So what happens as you’re driving along is that your phone’s MAC address is being picked up at various locations. And since the distance between these various reception points is known, it’s pretty easy to determine how fast you’re traveling. That’s how they come up with those time/traffic estimates. 

This data is anonymous but, in theory, the city also knows if people are speeding when the traffic is light.

This same technology is being used by many retailers and shopping malls to track how people move through their spaces. It’s used to see, among other things, which merchandising strategies are working and what synergies one might be creating (or not creating) with the tenant mix.

But getting back to traffic, there are obviously ways to collect traffic data without any additional physical infrastructure.

As I was about to leave the suburbs and head back downtown, my phone somehow knew I was about to do that (perhaps because I was stopped at a Starbucks near the highway) and so it decided to tell me this:

It wasn’t the best notification to receive on my phone, but I was impressed nonetheless. This traffic data is collected using GPS data transmitted from mobile phones using Google Maps, Apple Maps, and so on. Clearly we’ve come a long way since the days of manually leafing through a thick Perly’s.

At the same time, it feels like we are still pretty far away from solving the problem of urban congestion. Every big city in the world is grappling with this issue. 

Part of the problem, I think, is the belief that there’s some sort of silver bullet – more highways, a magic smartphone app, and so on – that will enable everyone to be able to drive around in their own car by themselves. I don’t believe that’s possible in big cities. And the sooner we get away from that toxic thinking, the quicker we’ll solve this problem.