iPhone X: How to disable auto-brightness
Hidden deep in the Settings app is the option to turn off auto-brightness.
Instead of letting the iPhone X automatically adjust how bright your display needs to be, Apple has tucked a toggle to disable auto-brightness into the Settings app.
It's a bit hidden, but here's what you need to do: Open Settings > General > Accessibility > Display Accommodations and slide the switch next to Auto-Brightness to the Off position.
Pay close attention to the warning just below the toggle. Because the iPhone X uses an OLED display, screen burn-in is inevitable, and by disabling auto-brightness you can potentially cause harm to your screen. It's up to you, of course, to decide if the risk is worth it.
Mobile Guides
Phones
Foldable Phones
Headphones
Mobile Accessories
Smartwatches
Wireless Plans