The main problem with the iPad is that all the apps have to be designed for iOS whereas a computer can run a multitude of software. (Although Apple claim the iPad Pro can do the same as a computer, it can’t, as anyone who has tried will tell you)
If you want something with an optimised touch screen that can be put on the music stand (Like an iPad can) then there is still no substitute for a 2 in 1 PC, (Apples refusal to implement a proper touch screen interface in their MAC OS is really hampering their sales) or the Surface type PCs.
For arrangers where convenience is required, then the iPad is great as it is easy to use, (Just like an arranger) but if you want to go above easy/moderate play then it is completely out its depth. (There also dammed expensive for what is offered)
As always, try before you buy, because when it comes to resale (If you find it doesn’t suit you) you will lose a chunk of cash, even on an Apple product.

Bill