Hah, I used to do that too, however I changed it so double-press of the side button toggles the flashlight instead. I find this to have much better ROI.

For camera, turning the screen off while camera app is open means I can just press the power button and slide up, and I'm back in camera app (unless Intenty interferes).

For flashlight, having a quick key (that works even when the phone is locked) is a qualitative change - I use the phone flashlight much more often, now that I can casually turn it on and off with zero effort, like a traditional torch. There are actually two major use cases I have for that daily:

- In autumn/winter, by the time I pick my kids up from the kindergarten, it's already dark. There's a stretch of pavement that's pitch dark, so I just casually light it up as we walk over it.

(That was the driver behind me changing the button mapping from camera to flashlight; having done that, I now instinctively turn the flashlight on and off as I walk, lighting up dark spots.)

- Have you ever tried to read something from a phone while walking at night? It's a big problem - the screen pretty much blinds you, unless you turn the brightness down to minimum. You can't read and monitor ground under your feet at the same time. However, if you also turn on the flashlight, the brightness of the screen and the light reflecting off the ground are similar, so reading becomes comfortable and you regain awareness of terrain.

I figured out that trick long ago, first with Kindle (Paperwhite) - I'd put my phone against the back of the Kindle, turn the backlight on the reader, and the flashlight on the phone. But it works even better for reading from the phone itself.