Is it possible to access data from the proximity-sensor of the iPhone surface?

Question

When you hold the iPhone to your ear, it detects that there's something (proximity-sensor) and switches off the display.

is it possible to access this sensor in an iPhone app?

Answer 1

It is possible via undocumented System calls, this is how Google's voice search works on the iPhone to start listening when it is close to your ear (or so i'm told). The API isn't publicly exposed though so although google got the app on the store your app might be subject to more scrutiny.

Sorry I can't tell you exactly what the calls are.

Answer 2

I don't think so.

Rather, there aren't any published API's for it.

Google's voice search uses it, but that caused some fuss as they apparently used some unpublished functions.

http://www.iphonehacks.com/2008/11/iphone-app-news.html

EDIT:

To clarify, there are published API's allowing you to turn it on and off, but nothing that will allow you to detect when it has been triggered.

Answer 3

The answer is yes. See the comments for working code: http://stackoverflow.com/questions/165539/iphone-proximity-sensor