I have a an iphone, but it's a love/hate affair for me. Yes, they're useful for somethings, but I hate needing to carry it all over with me. For the most part, I lock mine in the safe once I'm onboard.
As Dave mentioned, there are computer terminals that are available to us and I use them, not my phone. Lots easier to type on for an old lady....hahaha!
And yes, a program is delivered to your cabin each evening....you don't need your phone.