My favorite ipad GPS is MotionX, and yes, it wants a connection to the internet. Being cheap, I use my iphone as a hot spot to accomplish this.
But there are other Apps that don't need an internet connection at all, they completely load into memory. A few are: Google Maps, Apple Maps, and CoPilot GPS. All three do a good job. I like CoPilot best of those three. There are others, too.
But you still need a method of getting the GPS location. There are physical add-on devices, as someone mentioned earlier. Or an ipad that has the capability to connect to AT&T, Verizon, etc. have the capability built-in. Or someone else mentioned something about a bluetooth connection to the phone, I haven't tried it, as I don't need it.
If you were to see how nice any of the above look on an ipad, you'd never want a dedicated GPS again. I'm using mine to velcro my ipad to the front of the GPS, so that I have a mount.
