Vincent Teoh from HDVTest just did some extensive testing of the iPhone 12 Pro screen, comparing it with a $30K Sony professional reference monitor. He was blown over by the color accuracy. One test had better results than the $30K sony. It hit 1100 nits in peak brightness, 800 nits full screen. He discusses problems with Doby Vision: the lack of Youtube Dolby Vision HDR support, inability of Airplay to send DV to an LG OLED. Sending to an Apple TV will give you HDR, but not Dolby Vision.
For the best display turn off auto brightness and set to maximum brightness to get to the 1100 nits.
For the best display turn off auto brightness and set to maximum brightness to get to the 1100 nits.