I found this out the hard way. Typically, I keep my device brightness at low levels while indoors but still use auto-brightness, mainly to save on battery life. So when I went for the mail this past Saturday while reading an article on the new iPod, the screen quickly became unreadable when I stepped outside. I figured I either didn’t have the auto-brightness setting on or it wasn’t working — actually, that was my first thought: The sensor was broken. Unfortunately, since I couldn’t read the screen, it was impossible to even find the Settings icon.
After getting the mail and coming back inside, I went into the Settings and noticed this: No auto-brightness setting, just a manual slider.
Well, that sucks a little. One of those unsung features of the iPhone and iPod touch I love is the ambient light sensor, and I rarely ever change the brightness of my iPhone. Kind of a shame that the iPod touch has now lost this functionality.