Did a bunch of research and decided on the iPad Air 2, Wifi. It's working well, but today I tried out the feature where you set the home point to the remote's location. Pilot popped up a message saying "The mobile device's GPS signal is weak and its location cannot be acquired". Turns out the Wi-Fi version of the iPad Air 2 does not have GPS. Luckily I'm still in 30 day return window so it's going back and I'm getting the cellular version with the GPS.