It is logical to put TouchID on where tr home bottom is on iPhone. Because that is where your thumbs are when you holding it. On iPad, not so much. TouchID meant the easy way to do things. However in order for you to reach this sensor, you need repositing the entire iPad or stretch your finger. It realky defeats the purpose. Yes, you can authentic your Appple Store purchases, Apple Pay purchase, however every time you need do so, you need to repositing the iPad, this is not very cool. I am also not too sure how useful TouchID on iPads. It seems without NFC, Apple Pay on iPad is pretty much half backed. Also Apple could expand functionalities of this NFC chip in later software update, without NFC onboard, it seems iPad Air 2 and iPad Mini 3 gonna miss added functionalities. That just me. I do really think TouchID need at somewhere more easy to reach.