Triple-click Accessibility shortcuts
Another accessibility setting that could come in handy is the Accessibility Shortcut, which can be found by going to Settings > General > Accessibility and then scrolling right down to the bottom. Tap 'Accessibility Shortcut', and you'll see a menu of options.
Ticking selected features in this list allows you to activate them easily by triple-clicking the Home button. You can invert the colours of your iPhone for better visibility in low-light, zoom in to tricky-to-see parts of the screen and more.
(If you've selected more than one acessibilty feature to be accessible via triple-click, a dialogue box will pop up and ask which one you want - it doesn't apply them en masse.)
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