Google tracked his bike ride past a burglarized home. That made him a suspect.

“I was using an app to see how many miles I rode my bike and now it was putting me at the scene of the crime,” the man said.

[His lawyer] dug around and learned that the notice had been prompted by a “geofence warrant,” a police surveillance tool that casts a virtual dragnet over crime scenes, sweeping up Google location data — drawn from users’ GPS, Bluetooth, Wi-Fi and cellular connections — from everyone nearby.

NBC News