[mathieuh]

You can add privacy zones around locations so when people look at your activities your line just disappears inside the radius of your privacy zones.

I have ones around my home and where I work. No idea if that affects whatever data they sell (I doubt it, since you can still the full activity yourself even with a privacy zone), but stops people finding where you live/work and nicking your bike

[egwor]

The fact that an area is made private is also a piece of information. I was thinking that you could use that to track down sensitive areas.

[muldvarp]

Unless I'm missing something you can easily triangulate the center point of the private area.

[ashtonkem]

That’s effective on an individual level, but tricky to enforce at an organizational level. It’s not like it would be wise for the DoD to log into Strava and setup a privacy fence around every sensitive location.

[bluntfang]

you're essentially telling strava that the privacy area is very important to you (ie your home, work, etc) and they are probably selling that fact.

[pbhjpbhj]

What a great signal for thieves too - this user has enough disposal income to have a fitness device, and is worried about being tracked, they must have good stuff.

Presumably you could filter by average speed and only get people with expensive bikes too.

[sitkack]

You could also tell who from the public data has a private area, how long they are in it and when they leave it. You could do graph analysis to find folks on 20k bikes (correlate by zipcode) traveling at > 20mph with other folks that also have privacy areas.

If you find that > 3 of folks in that clique are close together and somewhere else, probably having a group event, many of them may not be in their "privacy area".

Anything that collects your location data is a shtshow when it comes to operational security. Even having one friend with poor GNSS hygiene can expose an entire network of relationships.