Last Updated: Jan 03,2010
Both the Car Dock and Multimedia Docks (aka the bedside dock) have magnets in them. When in close proximity to the back of the Droid (slightly off-center) the Droid's display will change, depending on which pole of the magnet is against the Droid body.
The advantage of Motorola's manufactured docks is that they will allow the charger to be used simultaneously -- great for using the GPS in the car (battery-eater) or for all-night bedside use as a clock.
I decided I didn't need to see the face of the clock at night, so just mounted a small magnet in a strip of .04" thick styrene and place the Droid on it, back down, on my nightstand. Works great.
Hope that helps.
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