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This may have already been mentioned, but with Apple pushing to ‘console quality games’, on the Pro models, at least, it’s possible the capture button might actually be used like the capture button on the Switch. Used to quickly capture screenshots and screen recordings, rather than as a camera shutter button.

jMc
 
The additions of buttons will make the phone design ugly. Instead, Apple please focus on removing the notch/island and also making the camera bump smaller.
 
I will capture your thoughts and meld them with Tim's. Creating The TimothyAppleAI, and we think you're gonna love it
 
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