Yeah, there are apps you can download on your woman's phone to transmit the location. I think Google has an app that does that already, and there are probably a bunch more...
BUT
You're going to need to activate that on her phone.
AND ALSO
I dunno about your girlfriend, but if a boyfriend ever did that to me I would dump his ass faster than you can say 'smell ya later'.
It's such a big invasion of privacy and really really creepy. You're wondering about going out on a date with her, and yet you want to monitor her?? That sounds like some restraining order sh*t right there!