Is there a standard way to get at "turn the screen white and the brightness up"? I used to have a torch app that had that mode (presumably, lower power than driving the flash LED), along with a few others (like a night-vision-preserving red screen).

Hardly the most challenging app in the world, but it was worth the $.99 I paid for it. I probably could have written it myself, and while I personally would likely have made it free, I felt ok giving somebody a tiny tip for it.