This is a physical heatmap of where I spent my time in the past 6 months, based on my phone tracking me. It's built with the ArcGIS JavaScript API and a lot of fiddling.

I utilized the ArcGIS QuickStart Guide as a baseplate for how to use the API, but expanded from there on my own using my imagination and the API docs.

The data is my Google Maps location history, sourced as a JSON using Google's Takeout personal data extraction tool. It was then converted and cleaned as a CSV; huge thanks to SQLify for allowing me to convert such a huge file. The file is hosted on AWS S3.

So, turns out the ArcGIS JavaScript library is a HUGE pain to work with. I spent hours and hours just screwing with stuff to try to get it to display simple dots, and there are very few Stack Overflow / forum posts / etc for debugging the plethora of weird and unclear bugs it spits out. I think if I were building a map like this in the future, I'd want to just leverage the actual licensed software to make it.

I guess another thing I learned was the benefit of cleaning your dataset earlier: for quite a while I was keeping all of the data intact, in case I wanted to adjust the visualization based on what I saw. However, a lot of it wasn't useful -- and it made cleaning and passing around a 40MB data file way harder than it needed to be.