I purchased Keynote for my iPhone4S but when I tried to download it to our new iPad, it's not listed under "Purchased Apps". Do I need to purchase separate copies for both my phone and my iPad? Thank you.
Are you signed in using the same Apple ID that you used to purchase
on the iPhone4S? You should not have to purchase again for an iDevice,
but would have to purchase to use on a computer running OS X.
Yep you need the same apple id on both devices. Since you already bought it you can install from purchased.
Retrieving data ...