Thanks in advance.
I got the information about the iphone sensors from http://ipod.about.com/od/ipodiphonehardwareterms/qt/iphone-sensors.htm. But I didn\'t get info
Here's a link to a description of the ambient light sensor hardware with example code that shows how to access it.
It is possible, and the framework is public.
You can activate the connection to the sensor like so :
[[UIDevice currentDevice] setProximityMonitoringEnabled:YES];
BTW, it doesn't seem to be using the light sensor, because proximity sensing would tweak out in a dark room.
However, the API call basically blanks the screen when you hold the phone up to your face. Not useful for interaction, sadly.
Here is a guide about iPhone sensors : iPhone sensors