Hi, if you mean the adapter cable to connect the elektrons via usb cable to the ios device, search for apple cck.
Apple camera connection kit
There are several topics on here about it.
This one for example:
Some newer apple devices have usb c already and one will only need an usb c hub in this case.
Be aware that on ios only one device can act as an audio interface/soundcard at a time, afaik…