So I just did a fresh install of iOS 8.1 on the iPhone 5s and a wifi-only iPad Air. So far, working well. Wasn't familiar with Facetime. I get a cell call, and damn if it wasn't the first time I heard the iPad ringing. My first reaction was, wtf? Was even more surprised when I was able to answer the call on the iPad, and even conduct the call using a wifi iPad, didn't even need a headset. (I say this because I haven't researched anything concerning 8.1, I simply did the upgrade.) So I assume this is the Facetime functionality, yes? No matter what it is, it's been working great so far, and I didn't do anything to set it up other than the fresh install and reestablish my accounts. Good job Apple.