Oldest Ipad generation that it would run well

Hello everyone, Im pretty excited to get Touchable.
I also need an IPAD for it but I’m in a very limited budget. Which is the oldest version of Ipad this would run seamlessly?
Thanks so much community <3

iPad Air 2 is still a capable iPad & can be found quite cheap on e-Bay these days. Saying that I have touchable installed on an old iPhone 5c on ios 10.3.3 & it seems to run ok, although i wouldn’t recommend it as the screen is so small. So anything that can run 10.3.3 should be ok, but an air 2 would be the lowest I would consider going for as a daily driver.
It may run on ios lower than 10.3.3, but I can’t verify that…