Just got my iPad Air today ! I have the At&t unlimited data plan for my iPad from way back and have faithfully paid it every month. Anyway, here's how I got mine over to my new iPad Air with No Problems, all by my self. One caveat, you will need to already have an online account in which to view your At&t account. After setting up your iPad Air with iTunes and all that... DO NOT attempt to setup your cellular account on your iPad Air. You must sign on to your At&t account and click on edit your account (or device). And then go to your New iPad Air and find the IMEI and ICCID numbers located in the settings. You must then change the IMEI and ICCID numbers on your At&t account online to match those on your new iPad Air and click save. It will tell you it may take a few minutes to update your account. Make sure you have your Wi-Fi turned off and your cellular turned on. You probably won't have a signal yet, although it may say LTE in the upper left on your device. Make sure your in a room that gets a good signal. Power down your device. Wait 5 minutes. Turn your device on. You should have LTE service and now with the number of bars lit up ! If you check your cellular device settings, it should read that your account is Unlimited Data Plan for $29.99 a month. Mine was incredibly easy and took 10 minutes. If you try to activate it on your iPad Air, the only options you'll get are the current plans and you'll freak out like me, just hit cancel !!! and follow the above. Enjoy ! Let me know your experience !