vaqm

it does make sense, if you'd like your iOs device to behave as a (sort of) giant Touch Bar check Quadro out... (http://quadro.me)

Did you try Quadro (http://quadro.me) instead? You need an iOs device tho, Android support is not yet available

This has exactly what you are looking for, including USB support: http://quadro.me

You don't need to create one yourself http://quadro.me

there's actually a sort of external Touch Bar in case you need one http://quadro.me