Why it’s Breakthrough: It’s an iPhone App that converts your phone into a stethoscope. Now you can capture your heart rate and even see it as a phonocardiograph display.

The Story: iPhone apps just keep getting better and better. This one, from Peter J. Bentley, in association with the software writers at The Undercover Scientist, is a really smart one. Thanks to the iPhone’s built in microphone, by placing it directly on your chest (it must be done against the bare skin), and by listening in with your headphones, you can hear and record your heart rate. Plus, the iStethoscope comes with a shake-activated phonocardiograph. By giving the iPhone a shake, you can listen to the last eight seconds while also watching the phonocardiograph display. This display can then be emailed (presumably to your doctor, though you may have a dear friend who’d love to see your phonocardiograph).

According to the site, the iStethoscope has other applications. Thanks to the sensitivity of the iPhone’s built-in mic, you can pick up exactly where those pesky birds are nesting in your wall, or where that leaky pipe is under the floor. Or, you could just listen in on that meeting in the next office, but you will have to be prepared to explain yourself when someone asks you why you’ve got your iPhone up against the wall with your headphones on.