A useful piece of research diving into the continued fragmentation of viewport and screen sizes across the web. I was actually one of the data points, as I saw the original call to arms (a clever microsite that did nothing but log out the current viewport dimensions, which were saved to a back end somewhere), and had been wondering what would come of the experiment, so it's nice to see it written up in such an interesting and creative way.

The results are not overly surprising, but I particularly like the comparison between common design tool "breakpoint templates" and how often those values were actually recorded. Spoiler: it isn't very often 😉

On the size of the dataset:

We gathered over 120,000 datapoints with over 2,300 unique viewport sizes.

On how fragmented even a supposedly locked-down web experience is, where an iOS browsing session may take place in Safari, an in-app browser, or even the new 3D preview:

Even on one iOS device, there's a minimum of 3 environments a website could find itself in, based on operating system states.

On how breakpoint-based design results in a worse overall UX:

If however, you tend to build with very specific breakpoints and hard values for typography, sizing and spacing, you might find that even with the best intentions, you’re not providing the optimal user experience.

Instead of making design decisions on strict, limited breakpoints, keep in mind the sheer amount of fragmentation there is in viewports.