I always wondered how Google Maps knew traffic conditions. Today, there’s a blog post where they explain it a bit better.
Basically, they simply have all the phones running Google Maps with GPS send back data as to a) where they are and b) how fast they’re moving. Both of which GPS gives you more or less by default.
It’s a clever idea, and I like it, but it fails in a couple of major ways, IMO.
Firstly, when I use Google Maps on my phone, I tend to not leave it open. Google Maps is fine, but it’s not a very good navigation system. It’s just a map. A real navigation app is worlds better. I recently got Navigon Mobile Navigator on the new iPhone, and it’s pretty slick. Thinking about a dashboard mount for it now, actually.
Secondly, this system relies on a lot of people having Google Maps open and running and sending back data. If nobody with Google Maps running has been on your street recently, you get no information.
What Google really needs to do is to open it up as an API. Let other navigation system manufacturers both send and receive traffic data from the Google Maps system. It doesn’t have to be complex.
Any good navigation app knows your location and speed, so a simple way to send that info could be made easily enough. The problem, of course, is allowing third parties to use the data.
Google Maps works in layers of images, which is one of its major shortcomings, IMO. The street views are images. The terrain are images. Just big sets of tiles that get displayed next to each other. And I’m almost certain that this traffic thing is just another set of images they’re generating or updating. For navigation providers that use 3d views and such, they don’t need that stuff in the form of images, they need it in the form of data. What streets are busy? How can that information be used to improve the navigation? Etc.
Google is generally pretty good at opening up their APIs to third parties. However, they’re generally not good at providing data in different forms. Most of their APIs are “this is what we use, if you need something else we don’t have it” sort of thing. Hopefully, the Google Maps team will see the light here and realize that to get good data, you have to give good data, and start pushing in that direction. Because open traffic data would be pretty cool for everybody.