Decoding Vibrations From Nearby Keyboards With Mobile Phone Accelerometers [pdf]
While interesting, I don't view it as having much of an impact. Page 6 states that there was a significant training period for their machine learning algorithm that involved sending the bluetooth from the keyboard through the phone to train it.In the real world, if you have compromised someone's phone and have access to their key strokes through bluetooth, why do you need this method at all?  Even in some contrived circumstance where it was more feasible, it would probably be better 100% of the time to try to compromise the phone's bluetooth, audio, camera, or wifi capability before targeting the accelerometer and then hoping that they happen to leave their phone close enough to the keyboard and hope that your algorithm can decode keystrokes on a keyboard that it has never heard before, which may also be a type of keyboard that it has not heard before.All in all, it's a cool experiment which shows that we can do some interesting and non-conventional stuff with accelerometers, but it's not practical in the slightest.