I've found that my iPhone is pretty much useless for tracking, since he batteries run out so fast if it isn't in airplane mode. I miss my android phone. It actually tracked well and had decent battery life. I used to put it in airplane mode, then turn on the GPS.
Check out the Bad Elf for the iPhone. I've used it for years, but it won't work with the iPhones stock moving map. You have to use it with another mapping app for it to work in airplane mode.
It even works in the cockpits of some airplanes. I used Bad Elf with my iPad for a long time with pretty great success.
