Flickering iPhone 13 screen

Is the auto brightness is on ?

if so this is a expected behavior!

in additional If the interior temperature of your device exceeds the normal operating range, you might notice these changes:

• Charging, including wireless charging, slows or stops.
• The display dims or goes black.
• Cellular radios enter a low-power state. The signal might weaken during this time.
• The camera flash is temporarily disabled.
• Performance slows with graphics-intensive or augmented-reality apps or features.

here are some steps to adjust your iPhone screen brightness ☞ Adjust the screen brightness and color on iPhone - Apple Support

I have a 13 and the same thing happened after I updated the iOS.

I’ve tried restarting it and adjusting the brightness, but it’s still “flickering”. I hope they figure it out soon, because it’s almost impossible to read anything on my phone with the brightness hopping around.

Hey there,

How exactly the screen flashes?

try restart your iPhone ☞ Restart your iPhone - Apple Support