Thanks for the advice Demon, but I prefer the low tech way. I try to depart for my session roughly 90 minutes before show time. I will usually arrive a little too early, but that is acceptable to me. I fill in that time with last minute grooming, donation, and clothing check. Comb? Breath mints? Envelope? Check.

The location will usually have a public bathroom. The restrooms in high end locations are almost always spotless. I use them for last minute necessities. If there is still more time on the clock, I call the provider to let her know I'm at the gate.

This will also save you from having to speed to your session and attract LE. Do your homework and know where the speed/red light cameras  and LE speed traps are in your area. I've noticed less cops with radar ever since speed cameras started popping up everywhere.

...is it better than google maps?

Be careful how you have it configured, I have friends who that app posts on their facebook automatically where they are heading to and what time they will be there.