I have got a suggestion
When i sit in my car, i give my phone to my holder and turn on Waze. It works perfectly, charge and so on, but when i leave, the waze is still on, tracking everything (GPS on) and eating my battery.
What about some feature, when disconnected from charging turn off Waze, or when standing on one place for more than 10 minutes turn it off?
Also i have got one more suggestion, blink display (on red f.e.) when speaking. I often listen music in my car loudly, so i don't listen to my phone. In this case i would know that it is speaking and there will be a police or there will be the turn i have to do.