When we started connecting professional audio equipment with iPhones to support musicians on Clubhouse, we had to resort to devices like the iRig 2 to break out the return channel and to lower the signal from line-in to microphone levels. When we got support for USB devices in Clubhouse, there was still the issue with reliably connecting them to iPhones.
Many sound devices are powered through their USB ports. While I can connect a Shure MV88+ to an iPhone, the Shure MV7 requires additional power. This can be supplied via the Apple Lightning to USB 3 Camera Adapter. The name is a little bit misleading because iPhone would initially only download photos and videos from cameras through this adapter. Today, you can attach all kinds of USB equipment, including professional audio equipment.
There are two differences between the Apple Lightning to USB Camera Adapter and the Apple Lightning to USB 3 Camera Adapter. The newer adapter supports USB 3 speeds and powers the devices with an additional Lightning cable. I recommend connecting a 12 W (5 V * 2.4 A) power supply instead of a USB C PD power supply since that tries to switch to 9 V which is unsupported by many USB devices.
[Vielen Dank, Roman!]