I've noticed that many devices come with automatic brightness settings for their displays if they have a light sensor. I find myself loving it on both of my phones, since it usually means that I get to have a comfortably dark screen in pitch black rooms, while having the screen pop out under bright, possibly direct sunlight without any repercussions for the most part.

I don't use it on my laptop, though, as it's too slow to respond. I just set it at 75%.

Sometimes this made me wish that the 3DS had automatic brightness, too. When done right and responsive enough, it's great for any time of day. What do you think of it?

I actually use it quite often. It so that when I wake up at 3 am and can't fall back asleep, I don't blind myself with the full out brightness of my phone. I also like just checking the time while outside with the sun, and it's not glared out, so I can still see it.

I have automatic brightness on my iPod Touch, and while I like it, it seems to be very slow to respond, and seems to have a bias towards being darker; for instance if I cover up the sensor it almost immediately goes dark, but if I hold it in direct sunlight it takes a while to go bright. It also starts on the manual setting which for some reason I have set to very dark.

I have auto-brightness on my HDTV and phone, but don't use it. I should start using it for the phone, but I don't use it for the TV cause it looks weird watching a program while the auto-brightness keeps adjusting the brightness on-screen.

Yeah I have auto brightness. It helps a lot, but there's only one situation that I found it terrible. I was texting and the lights went off in the movie theater. Then some derpy guy yelled at me in the middle of the movie for my brightness. Oh well, my fault

I have never used. I didn't find it as useful since I was never in a situation that required auto-brightness.

I've never actually required it, but it's useful and possibly better for my battery. When I was at a fair, I was outside all day, and I couldn't tell whether auto-brightness was working or not, so I cranked it up to max brightness, and then that sucked the life out of my battery.

I use it whenever I'm using my laptop in a dark room (usually in bed, sometimes in class), as it's much better on my eyes. I tend to turn it off once I'm back in a normal room, though.

On mine it gets darker when I'm trying to look at something dark and brighter when the screen is mostly white.

Whoops, now I get what you're talking about. I realized my iPhone does that, and it does it well. Except I want to use my iPhone's screen as a flashlight in the dark sometimes.