Did you know that you can use a separate audio interface with your iPad?
Well you can!
If you do a quick Google search for iPad Audio Interface, you will come up with plenty of suggestions for interfaces that will work with your iPad.
My current weapon of choice is the Steinberg UR44, which I’m using with my MacBook Pro and my iPad Pro. It allows me to attach guitars, mics and midi keyboards to either device, which in turn means i can input any audio signal into whichever DAW i’m using. Currently, these are Cubase 9 on the Mac and Cubasis on the iPad, but the same setup would work equally well with ProTools and GarageBand respectively.