Does the iOS app work on Tablets?

I’m thinking about getting a basic setup for my Dad for Father’s day. He doesn’t have a Smart Phone, but does have a an iPad. I believe I read somewhere that it wasn’t compatible with iOS tablets. Can anyone confirm/refute this?

The iOS app works great on iPads! The one caveat is that it’s not a tablet optimized app.

What does it mean it’s not tablet optimized? Does that mean that, like when running on an Android tablet, the text is ‘sized’ for a smaller screen?

It means that the app scales to the larger screen but won’t fill it up entirely. Android apps not formatted for tablets will fill up the screen entirely but some UI elements might look strange at that scale.