UPDATE:
See also Mayayana's related reference just now in the Windows newsgroup:
o Do you have a trick that edits & saves the HOSTS file in a single command?
<
https://groups.google.com/g/alt.comp.microsoft.windows/c/HXAESt4-M-k>
Which said that some of the bluetooth surveillance is via the weather app,
the Target app, the WalMart app, etc., unbeknownst people using those apps:
o In Stores, Secret Surveillance Tracks Your Every Move
<
https://www.nytimes.com/interactive/2019/06/14/opinion/bluetooth-wireless-tracking-privacy.html>
The beacon graphic alone in that article Mayayana suggested is revealing:
o <
https://int.nyt.com/data/videotape/finished/2019/06/1560523217/desktop_crop1-1254w.mp4>
Worse, that cite referenced this article which describes another gotcha:
o Google can still use Bluetooth to track your Android phone when Bluetooth is turned off
<
https://qz.com/1169760/phone-data/>
That gotcha is that you don't need to be using _any_ apps to _still_ be
tracked by bluetooth beacons (if I read the article correctly that is).
o <
https://cms.qz.com/wp-content/uploads/2018/01/bluetooth_scanning_grid_andriod_004.png>
The article claims you don't need ANY bluetooth apps to be tracked by BT
o At least on Android phones (they don't mention iOS in the cite I skimmed)
o Google can still use Bluetooth to track your Android phone when Bluetooth is turned off
<
https://qz.com/1169760/phone-data/>
"And last year, investigators at Quartz found that
Google Android can track you using Bluetooth beacons
even when you turn Bluetooth off in your phone."
"When Location History is activated, Android phones try to send a
plethora of nuanced information back to Google...
including nearby Bluetooth devices."
"A spokesperson for Google confirmed that turning off Location History
would stop a phone's reporting of nearby Bluetooth beacons"
Hence I suggest people add the necessary shortcuts to your Android
homescreen shortcuts folder, so these Android settings bubble up high.
o Quick tutorial for creating Android homescreen shortcuts using custom icons
<
https://groups.google.com/g/comp.mobile.android/c/if4FD2NFEnk>
Note: You can make a shortcut to most settings inside Android & the apps.
o Is there a way to make an Android homescreen shortcut to any given settings page such as the battery status?
<
https://groups.google.com/g/comp.mobile.android/c/_1oTdgCIpkc>
--
See also this (much older) article on being tracked & not knowing it:
o Your Apps Know Where You Were Last Night, and They're Not Keeping It Secret
<
https://www.nytimes.com/interactive/2018/12/10/business/location-data-privacy-apps.html>