Is someone listening through your phone?AzmanL/Getty Images
Hackers can eavesdrop on conversations near smartphones by measuring sound vibrations with the handset’s built-in motion sensors.
Experiments had previously shown that the gyroscope and accelerometers in smartphones, collectively known as an inertial measurement unit (IMU), could detect sound vibrations in the air and listen in on conversations. This means an app that doesn’t have permission to use the microphone could get around this by using the IMU as a makeshift sound sensor.

To combat this, Google set a limit…