The head-up display looks really cool. How do you keep it from falling?
I had Maps on while on the bus. As the bus moved, it indicated that I was in the middle of an open field. How could that happen? Is it problem with the app or the phone? Do garmin car gps have this problem?
As for power, if I put the iphone to the usb port of 12v port of the car, will the phone run out of power? In other words, will power usage faster or slower than charging when the iphone 6s+ is used as a car gps?
Depending where you are, all GPS devices can experience congestion of signals, particularly in city centres. GPS requires a decent line of sight to the satellite. A cluster of tall buildings, thick walls inside a car park tower, underpasses, tunnels or lorries all around your car can confuse your device, which doesn't adapt to your location in time. Nasty when you are negotiating a tricky roundabout or junction towards main roads with no quick way back if you pick the wrong one but them's the breaks.
My personal experience running a 6s+ with Tomtom GO is that if you have the screen on full brightness, then you will do well to keep your battery level stable even with a 2.4A adapter in your cigarette lighter socket. Reducing the brightness to 50% or less will let the phone charge up even while navigating.
I used to have a TomTom. It was brilliant about 10 years ago. I was so impressed, I eventually upgraded to a TomTom Go 520. This had 'IQ routes'. Which essentially meant that it gave different time estimates for routes depending on the time of day. This was pretty good, but didn't distinguish between weekdays and weekends. Driving in central London at 8am on a week day morning is quite a different experience from driving there at 8am on a Sunday morning. After a while, I switched to the TomTom app. This was also great for a while, but v expensive for the initial outlay. I think I paid £54.99 for it. It provided updates for years, but I think they are now going to charge for them.
Tomtom is moving to a subscription model with a redesigned (dumbed down) app called GO. The good news, is that if you bought the standalone app, Tomtom will give you a free 3 year subscription to the new app, which includes HD Traffic and speed camera warnings. Those are a paid extra with the standalone app. I am using it until the subscription runs out then looking at my options. Nothing yet beats Tomtom's traffic alerts and rerouting and I have tried them all.
I tried Waze. It was junk. I would rather pay than have to rely on that. I am in the UK. It might be a better prospect in the US.