Apple Pencil support would be super cool on the iPads. Also worth noting, aside from typical handwriting inputs like Wacom digitizers, found in laptops like Lenovo's Tablet lineup, the MSoft Surfaces, etc, Wacom also makes pen tablets at a price point of less than $100USD, although they may be a little different to write on as they are just digitizers, and you'd be watching the screen to see what you're writing. Works great for art though!