That would be quite an implementation flaw if it didn't account for the phone's own vibrations. Lots of countries use widespread emergency alert messages frequently.
It's obvious to anyone that's written software for hardware sensors to ensure the hardware itself is not going to interfere with readings of other sensors. Don't tell the motor to run if the motor is already running type of issues. It's a fairly common bozo check
Typical Google product. Reminds me of a person who put a bunch of phones in a car and drove which caused Google maps to wrongly show traffic in that area. It was deliberately done though as an experiment
