With the rise of smartphone apps, users don't always know what features and functionality those apps may be using. Reports are coming out about various apps that use the phone's microphone (and, sometimes, camera) in somewhat surreptitious ways
to gather data. Now, of course, there are certain apps that people expect
to use the microphone or a camera -- such as music or TV show identification products. But it's a bit of a surprise that apps such as the massively hyped (and then quickly panned) Color (which is a sort of photo sharing/location-based info service) is making use of your microphone and camera without most users realizing it:
Color uses your iPhone's or Android phone's microphone to detect when people are in the same room. The data on ambient noise is combined with color and lighting information from the camera to figure out who's inside, who's outside, who's in one room, and who's in another, so the app can auto-generate spontaneous temporary social networks of people who are sharing the same experience.
Another app discussed is, Shopkick, which gives people rewards for walking into certain stores. While you might think it could accomplish what it needs with GPS, apparently the stores in question have special devices that emit sounds that you can't hear, the microphone on your phone can pick up, thus "confirming" that you really entered the store.
While the reasoning behind these may be benign, my guess is that most people would feel pretty creeped out about apps turning on either the microphone or camera, without explicitly warning the user and making it clear what's going on (or letting them choose to turn on those features directly). Mike Elgan, who wrote the article linked above, notes (obviously) that surreptitiously turning on your microphone can provide marketers with all sorts of useful data (ya think?), so we should expect it to happen more and more often. Of course, all this is making me think that my Android phone needs an app that warns me whenever the microphone is turned on and lets me block it... Anyone writing that app?