[titzer]

The accelerometer in most phones is accurate enough to detect individual footsteps. Phones also include a barometer that is sensitive enough to detect which floor of a building you are on. With dead reckoning based on accelerometers, calibrated by GPS, compass, WiFi, and barometric data, people can be located to within centimeters. Activity detection, mode of transport--ha, child's play!

If you run Android, turn off "high location accuracy". It uses all of these features.

[leoferres]

:) I really don't care that Google knows what I'm doing. What I do find amazing is that people are usually afraid of telcos for tracking, when it's more like you have to be afraid of Google and apps like Candy Crush...

[titzer]

You realize that with a NSL the US government can compel Google to disclose information on anyone and that the contents of NSLs are completely secret, right? Oh yeah, and Google operates globally and no one really knows what arrangements they have with the various governments around the world.

[eru]

Well, not sure whether turning off a setting in your phone would help you in that case?

They could probably compel Google to make the UI not reflect what the phone actually does.

[rurban]

Or even worse, arrangements with criminal and terrorist organizations, committing warcrimes all over. They now love to shoot you down with a drone based on Android High Accuracy Location Tracking, without any due process. They also love to block free travel without due process. It's called freedom (of civil rights, to block and terminate).