TomTom is the most popular GPS software for the Palm OS. The UI looks very similar to their standalone product and this is occasionally a bit weird because not all the treo's keys work. But they've done an acceptable job of integrating it.

If you don't have a GPS system yet and you drive, you should get one. Might as well get the one that integrates with the address book in your treo (no matter how clunkily).

One note: If you get a persistent "not enough free db cache memory to run this application" error when you start up TomTom Navigator, then you may want to install DBCacheTool and configure it to "free < 4M", "max < 4M", "App stop" and set "Navigator" in the "Apps..." popup.

We left home late to meet relatives at a restaurant, but thanks to the TomTom navigation software, we were provided with quick, clear directions, saving us even more time hunting around for our destination.

Combined with a bluetooth GPS and a Treo 650, this software provides a complete in car navigation system, complete with real-time updated maps and voice driving directions.

In my limited use so far, I've been a little disappointed that the voice instructions haven't been quite enough to figure out exactly which turn/exit to take, but combined with the onscreen info I had no trouble figuring out where to go.

What's really cool about the TomTom software is that if you miss a turn, it quickly recalculates the route based on your new location and direction and gives you the new best directions.

You can also ask it to avoid certain parts of the route, notify you when you are near a gas station or restaurant, and much more.

Tips:

- Make sure you buy the correct version of the TomTom software (one that will run on your Treo 650 PalmOS).

- Make sure you download and install the latest software upgrade from TomTom.com before trying to install this on your Treo 650. Following that tip would have saved me a half hour of wasted effort. (via joe)

I have TomTom Navigator 6 for palm and it is wonderful!!!!! No more getting lost, it runs great on the treo, etc. (via joe)