Recreationally overengineering my location history

https://overengineer.dev/blog/2025/08/19/overengineering-location-history/

by kickofline • 11 months ago

56 7 11 months ago

zacwest• 11 months ago

If you want to get location accuracy lower than 500m without significantly impacting battery life, you can use region monitoring. There's two paths:

1. Set up a region around the user's current location. If they exit it, note the location and set up another one around that location. This will give you around 100m accuracy, which is the minimum diameter of the monitored region.

2. Set up regions in various cardinal directions that nearly-or-just-barely overlap. If they enter one of those regions, note the location and set up another set around the current location. This can give you something closer to 50m accuracy.

For (2), this is how I did it in the Home Assistant iOS app, largely for zones that people wish to monitor which are smaller than 100m. You can find some of the annoying math here[1] (and there's tests all over for it), the logic for setting up regions here[2], and computing them here[3].

[1] https://github.com/home-assistant/iOS/blob/master/Sources/Sh... [2]: https://github.com/home-assistant/iOS/tree/master/Sources/Ap... [3]: https://github.com/home-assistant/iOS/blob/2dfbe3c0e52a30417...

nicbou• 11 months ago

That's a wicked cool visualisation. I love it!

I have underengineered a similar problem with Owntracks, a Python receiver logging the location to a daily GPX file, and a static site generator generating daily map pages out of that data.

My goal was radically different: have everything saved in standard format, along with my other synced personal files, and turned into a static site. The static site is a daily diary augmented with my other activities. Owntracks is multiplatform and absurdly reliable.

immibis• 11 months ago

Mine just runs mosquitto_sub | gzip > $(date --iso=seconds).gz

forever_frey• 11 months ago

Looks awesome and I love the approach! About a year ago, I went through pretty much the same process and built Dawarich, although it's only now I'm starting touching the topic of sharing location publicly, not just recording it for further visualization.

Great work!

datadrivenangel• 11 months ago

Very cool. I did a similar but much less engineered and artistically inclined visualization using Bokeh in Python a few years ago: https://github.com/DataDrivenAngel/GDataViz

physicles• 11 months ago

Love the visualization, and the scenario of sharing your real-time location with anyone is important. I don’t know if Uber has that built-in, but Didi (in China) does and I use it frequently.

If anyone’s looking for a more plug-and-play option on iOS, I’ve been using Arc Timeline for nearly two years and it just dumps reasonably accurate .gpx files into your iCloud Drive without using too much battery. I use it for visualizing working locations and other activities on a weekly timeline.

pvtmert• 11 months ago

Even though it is at overengineering.dev, loved this pragmatic and simple approach:

    I have implemented the most advanced client-side error-handling technique ever: window.location.reload().

In larger (stateful) apps, this is probably not what you'd want. But works for small, stateless apps...

Recreationally overengineering my location history

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