Not charging iPhone when using GPS apps I have GPS Drive App Motion X-GPS. I tried to use this app with my iPhone/iPad cigarette charger plugged in, but the battery is keep draining even with the charger to make this app almost useless for long distance driving. I used the charger without any problem with other apps. 

Why iPhone is not charging with GPS apps? Is this iPhone's known issue? Is this an issue with Motion X-GPS? Or new/better cigarette charger is needed to solve this issue?

I use Scosche that has 2.1A port, but it doesn't charge when I use this port with iPhone.
It's not a bug, it's just because the GPS app is using much more power then the charger can deliver. You should check the amp. of your charger. I have one of 2100 mA and I can use my iPad with Navigon while my iPad is charging.

This charger sold in the Apple Store will provide your iPhone enough power to both run the GPS app and charge at the same time.