How to submit UI ideas to Apple for consideration
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(rapid-successive) of the iPhone's power button (aka "side" button) could be intepreted by the iPhone to invoke an app or action that is user-configured (camera, etc.). Where is the appropriate forum to submit ideas as such ideas?
Solution 1:
All suggestions or feedback should submitted to https://www.apple.com/feedback/.
Select "Feature Request" under "Feedback Type"