According to blog information Ars Technica, Google confirmed today that the new version of the Google Mobile App actually uses an undocumented trick to gain access to the proximity sensor, a technique that has been much discussed and investigated by the iPhone developer community.
A company spokesman reportedly told CNet that the latest update to the Google Mobile App makes use of an undocumented API to obtain information from the iPhone’s proximity sensor, which allows it to activate the voice search function when the user touches the device to his face.
However, doubts about the API remain: how would Google get access to the sensor since it is not present in the iPhone SDK documentation? The answer to that and other questions may come up soon, possibly in a new version of the iPhone SDK itself.
Still, according to the blog, this is not the first time that Google has the chance to use undocumented APIs. In an analysis of Chrome’s source code, developers found traces that the browser would be using undocumented APIs on certain versions of Windows, with the aim of providing greater security against malicious websites.