If you’re a long-time Android user, you’re used to long-pressing the power button to (logically) power your phone on or off. For a while, long-pressing the button while the phone was on also enabled you to restart it, lock it down, or signal an emergency. (For a short time during Android 10, you could also use it to take screenshots.)
So you may have been a little perturbed if, after you upgraded your phone to Android 12, you found that long-pressing the power button did not bring up the shut-down menu but instead activated Google Assistant. This is something that was instituted with the new version of the OS, and it’s supposed to be A Good Thing.
You can still get the power and emergency menu by pressing the power and volume up buttons simultaneously — which may work for you if you seldom (if ever) need to shut down your phone. But if you’d rather have less awkward access to the emergency button or want to go back to being able to long-press the power button in order to shut down or restart your phone, don’t fret — you can change it back. Here’s how:
Open your Settings menu (by swiping down twice from the top of your phone and tapping on the gear button).
Select System > Gestures.
Go down to the bottom of the menu and tap “Press and hold power button.”
Toggle off “Hold for Assistant.”
And that’s it!
Incidentally, there are a number of different options for using taps and other gestures on the Gestures menu that you may want to take advantage of. For example, you can set Quick Tap (two taps on the back of the phone) to enable a number of features — for example, you can use it to take a screenshot, open a specific app, or even access Google Assistant (which is how I have it set so that I can keep the power button long-press for that emergency menu).
You can also arrange to press the power button twice to start your camera, go back to the old-fashioned three-button navigation at the bottom of your screen, or put your phone face down to turn on Do Not Disturb, among others.
All of these, and other features, can be enabled or disabled in the Gestures menu.