digital compass modules

[Schmidt András]

Sébastien Lorquet wrote:
> I'm not sure a magnetic sensor is useful when you have a GPS, because 
> a GPS can give you a heading as soon as the measured velocity is not zero!
It is true when you use it in a car when cruising with normal speeds. 
When you are using your GPS on foot (installed with a hiking map) your 
velocity's direction is not well defined enough and also when you stop 
for navigating you usually turn a different direction than you were 
walking. (I would use my device this way when hiking or geocaching -  
see http://www.geocaching.com/)

Also sometimes I get fed up with the GPS and navigate using old 
fashioned paper maps. A compass always comes handy ;-).