Researchers have discovered that you can log keystrokes from computers simply by placing an iPhone 4 – and probably any recent upmarket mobile/cellphone – near a user’s keyboard and monitoring the keyboard’s vibrations.
As documented in their paper, ‘(sp)iPhone: Decoding Vibrations From Nearby Keyboards Using Mobile Phone Accelerometers’, they could decipher complete sentences with up to 80% accuracy, using a dictionary of about 58,000 words.
A Georgia Tech University team used the accelerometer in an iPhone 4 to sense keyboard vibrations and determine what was being typed, without connecting to the user’s computer or peripherals.
“We first tried with an iPhone 3GS, and the results were difficult to read,” said Patrick Traynor, assistant professor in Georgia Tech’s School of Computer Science, “but then we tried an iPhone 4, which has an added gyroscope to clean up the accelerometer noise, and the results were much better.”