I've had the Charge and its OEM car dock for about a week or so and I've had some problems with it overheating the phone battery while charging and using Google Nav, but it only seems to happen if the sun is beating down on the dash. I'm working on some solutions (like adapting the dock to an A/C vent mount) so we will see.
But I've also figured out a neat feature of the Charge if your car has an Auxiliary input. Mine does, so I bought a 3 foot, 3mm, male to male audio cable which I use to connect the dock to the car. With the car radio switched to the Aux setting, the Google Navigation audio comes through the car speaker system rather than the phone which is awesome since I can never hear the instructions using the speaker in the Charge (or when I would use my old Garmin).
But since my car radio is set to "Aux", I couldn't use the radio (or my iPod). So I downloaded "Slacker" and the free app "TuneIn" to my Charge. TuneIn allows you to pre-set and listen to your local stations (plus tons of other stations). So now, I can listen to my local stations, or Slacker, or my iPod music I've loaded on the phone, while using Google Navigation. The Charge also automatically mutes the music when the Navigation app provides driving directions. To navigate or toggle between the Apps, you can press and hold the home button (or use the phone's pull down screen if you already have the apps running).
Now I feel like I did pay that extra $2,000 for the factory Nav System in the car. Pretty neat! In spite of the some of the problems I've had, this phone is amazing!
Rich
