Where's the ambient light sensor on the 4th gen Touch? I want to buy a skin (gelaskin) for mine, but it will cover everything other than the camera and the touch screen itself. I went to ifixit, but they didn't mention anything about this sensor. I tried to tilt my Touch on odd angles, and I don't see a hole like on the 2G/3G Touch, other than the front facing camera. Anybody have any ideas? I don't want to inhibit the sensor's function.