Recording live stage event with phone camera and mixer audio on iPhone

Namaste Everyone, I want to record a live stage event to my phone wherein video gets recorded from the phone camera and audio from the sound mixer, someone from the apple community please help me guiding for the same.

I watched a video on youtube related to this a few months ago which I couldn't find right now.

Regards,

Sudhir

[Edited by Moderator]

Original Title: is it feasible to record a live stage event wherein video gets recorded from the phone camera and sound directly from the mixer?