Android 16 Developer Preview 1 brings a handful of user-facing additions, but nothing major so far. On the Pixel 9, there's an "Experimental mode" display color.

In Settings > Display & touch > Colors, you'll find Natural and Adaptive joined by "Experimental mode."

It results in the screen becoming quite warm and yellow. The effect is pretty close to Night Light, which you can have enabled at the same time.

If Adaptive is the most vibrant option and Natural a step below, Experimental mode comes way underneath that. It's not obvious what the intention here is.

We're only seeing Experimental mode on the Pixel 9, with a Pixel 8 not offering it.