[godelmachine]

May I ask what screen recording app is he using?

[baloki]

It’s built into iOS nowadays, you can add it to your control centre via settings.

[josefresco]

I just discovered this, after my daughter told me about it. You need to set it to show in your control center first.

[dhruvrrp]

iOS has screen recording built in which stores the video in your photos.

It's the circle on the bottom right in the first frame of the video.