I use Anywhere Map on an IPAQ PDA and can recommend it. I, too, have a
character-based IFR Approach-certified GPS (Northstar M3), and
appreciate the extra situational awareness provided by a color moving
map.

I've used Lowrance Airmap GPS's and much prefer the display and upgrade
ability inherent in a software-only solution.

Anywhere Map is available for PDA's and for tablet or laptop (Windows
XP) devices. It isn't perfect but they are working on it continuously.
It offers terrain warning, vertical navigation and, at the moment, very
rudimentary approach capability. They've indicated that full approaches
will be available in a future upgrade.