How do popular routing gps/phones/mapping web sites update their route information?

Question

How do popular routing gps/phones/mapping web sites update their route information?

And do any phones send back data based on the users actual trip to allow the system to update route information?

Answer 1

What do you mean with "route information"? The map data they use to calculate routes is usually provided by companies Like NavTeq. They provide updates to the data on a regular base.

Concerning data collected by users, TomTom provides so called "IQ routes" which are based on actual traffic data. Meaning when you travel at 5am the system will likely suggest a different route compared to travelling during rush hour.
The required data was collected by the TomTom systems but AFAIK users have to manually upload it to TomTom or at least agree to provide the data when they do an online update of their system.

Answer 2

The two major players in this world are TeleAtlas, a TomTom subsidiary and NavTeq, a Nokia subsidiary.

IMO TomTom/TeleAtlas has the most advanced system. They operate a real-time system for measuring traffic flows, HD traffic. This takes into account data from other HD Traffic users, but also anonymixed data extracted from the GSM network. Now, in addition to the real-time view this provides, TeleAtlas also compiles a statistical average out of this; TomTom sells that as IQ routes.

Now it follows logically that if there's a lot of new traffic across a river, then probably someone built a bridge there ;)

In addition to HD Traffic and IQ Routes, TomTom also allows their users to report map erros and updates with MapShare. For many classes of changes (e.g. one-way roads or blocked roads, or changed roadnames), TomTom can use MapShare to immediately distribute updates for their maps without issuing a full map update. As a TomTom subsidiary, TeleAtlas presumably has access to these reported updates as well.