Why I Only Show One Weather Metric in the Chrome Toolbar

In building the Chrome weather extension SkyFeels, one of the challenging decisions was determining what the toolbar icon should display. Initially, temperature was straightforward, but adding air quality index (AQI) and UV index soon followed. Initially, the thought was to show all three metrics simultaneously. However, this proved to be an unwise approach.

The toolbar is quite small, and users typically don't spend much time scrutinizing it, trying to interpret multiple numbers, colors, and symbols. After testing various designs, it became clear that such an approach would diminish the icon's usefulness. The primary purpose of placing weather information in the toolbar was to allow users to quickly glance at it and understand it within half a second. If they had to stop and read it, they might as well open the extension.

Ultimately, the decision was made that the toolbar should present only one metric at a time - either temperature, AQI, or UV. Users can choose their preferred metric, and the remaining two are still accessible upon clicking the icon. While this decision may seem like a minor product choice, it significantly impacted the overall UI design.

The toolbar became a space for quick glances, while the popup became the area for more detailed information. Current conditions, hourly forecasts, multi-day forecasts, air quality, UV index, and saved locations were all important pieces of information that made sense once the user opened the extension. Trying to cram all of this into the toolbar, despite it being technically feasible, felt counterproductive.

The focus was on providing weather information "at a glance" with the rest of the details available upon opening the extension.

One of the key takeaways from this experience was recognizing that constraints can be quite useful. When working with limited space, every piece of information must earn its place. No room exists for adding additional cards or features without justifying their presence. This mindset has influenced the approach to UI design beyond the toolbar as well.

Now, there is a tendency to question whether certain elements need to be visible all the time, leading to a more deliberate approach to feature selection. Feature lists often turn into traps, as companies compare their products to competitors and feel pressured to add similar features. Instead, the focus should be on deciding what should be left out.

In the case of the toolbar, the choice was clear - one metric that is immediately readable rather than three metrics fighting for the same limited space.