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Comment by miahi | Hacker News Reader

Strava allows you to set places where it should not track (like close to home); not everybody uses that.

I have it turned on, but honestly it's not very hard to figure out where I live... it's in the middle of that circle where my runs oddly seem to stop

If you start and stop your run going different directions it's not too hard to figure out the central point between them, but if you start/stop from the same direction then it's not clear what the "middle" of the circle would be because the radius of the circle is configurable and unknown to viewers.

To expand on this, it takes three points to identify a circle, so you'd need to leave home and return from three different roads (at least at the intersection with the circle).

You can still potentially make useful inferences without 3 points. For instance, imagine the configuration where there is a single straight road that leads to your home (center of the privacy circle) - you can just extend the line where the GPS tracks for 5/8 mile (the biggest privacy setting) and infer the location of the home. Similarly, if you have 2 straight GPS tracks leading to your home, you can infer both the center and the radius of the privacy zone.

You may not get the exact street address, but you could definitely figure the block or the street. Maybe not super useful in a dense city, but that could leak quite a bit about you if you live in a suburb or rural area.

Pro tip: You don't have to put the center of the privacy zone to your actual living location.

Don't center the circle on where you start your tracking. Create multiple overlapping circles to further obfuscate.

And ride / run through the circles on occasion. These will show up in tracing confusing the analysis.

This isn’t in the iOS app at all. I wouldn’t be surprised to learn that many users never visit the website.

The iOS and Android apps are hamstrung versions of the web app. The web app is way more useful.

They’re also what 99% of their users use so they really meed to have feature parity on important things like privacy, especially given how trivial this would be (“fuzz n meters from my current location”).

Interestingly, this feature is one of the first I recall using on Android maybe 8 years ago. It was very visible and easy to turn on... Not sure why they made it harder to discover. Or have they removed it?

They do offer manual route trimming from both ends, too. I've found this useful mostly when I forget to turn off my watch after running.

I’d believe it needed work after a major rewrite and is still in someone’s backlog. They seem to have a fairly small dev team - probably busy with device support & other time-sinks.

I wish they had a way to do an auto-trim so my bike rides didn’t include GPS bounce leaving the building. CommuteMarker.com had auto-tagging for Strava rides but not auto-trimming last time I looked.

If you go to the Privacy section of the iOS app it's mentioned at the bottom with a link to the webpage ("Further customise your privacy..."). Not ideal you can't do it from within the app though.

Also it’s like 6pt text at the bottom of a long form. I really wish it was prominent.

No UGD (data) companies want to make it easy to reduce the amount of data they offer.

They do have the counter pressure of not losing users or inspiring government action. I’m not sure how this plays, for example, with the EU data protection laws but I’d bet there are some smart lawyers looking at this.

Strava apps are not perfect; they have a lot of settings in weird places. To sync with an ANT+ or Bluetooth sensor on Android you have to actually start recording an activity, and then press the small "settings" button in that page. Those settings are different than the ones in the main "settings". And then you add your HR sensor, record heartrate data for your workout and at the end you find that if you want it displayed in the app you have to pay :).

IIRC, it's just "place," singular; it only lets you set "close to home," not arbitrary locations.

You can set any number of places, and how large the blocking radius for each one should be.

I'd be curious if you're able to set up large privacy zones for the sensitive area case.

For instance, if I set a privacy zone centered on my house (or my military base) with a radius of 100 miles and all of my running activities are contained within that privacy zone are those runs automatically marked private? If I never run across the boundary then there's no issue of inadvertently exposing the privacy zone center point. Would Strava hide the GPS information but allow my run stats to accumulate? I don't think the feature is quite there yet but it could be close.

Or you could just not start tracking right at your house. Wait until you get to an intersection, for example.

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