How to screen record on iPhone 15

on a Mac? or on an iOS device?

for the Mac, please see How to record the screen on your Mac.

for an iOS device, please see Record the screen on your iPhone, iPad, or iPod touch - Apple Support.

but if you want to record the internal audio on a Mac, please let me know as there are a couple more steps involved.

Go to settings, find the control center tab, find the screen recording icon, then drag it to the top and then launch the control center on your iPhone, i.e. swipe from the bottom up, all these icons will appear there, click the recording icon and after 3 seconds your screen will start recording.

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