Thanks. I ordered a ACCK. It’ll do, because I can retrieve external clock and midi over the auxiliary midi input in H9 control. This works on my laptop, so I’m fairly confident it’ll work on iOS too.
Weird though that on a desktop (Windows in my case) we are give an option to choose a regular midiport as an alternative if H9Control doesn’t find a H9 device on the USB bus, anddoesn’t do so on iOS.