[bombela]

For what is worth, on my phone double click on the power button located on the side jumps into camera mode (even if locked). And pressing the volume down takes the photo. Then one click on the power button to turn off.

click-click, click, click.

And assuming the Google software doesn't decide to lag too much, it's quite quick to, and it reduces how much you touch the phone with dirty gloves.

edit: I should add that you still need one hand free to do so of course.

[qup]

FWIW it sounds like you have a pixel. Other androids aren't quite the same, but often have similar shortcuts.

The pixel is very quick to get the camera open, as you say.