This pie chart visualizes the aggregate distribution of Android, iOS, and BlackBerry OS users from a yearly US dataset spanning 2009–2023. The visualization displays three colored slices with white percentage labels and a legend. Built with D3 v6, it uses `d3.arc` for slice geometry, `d3.scaleOrdinal` for color mapping, and `d3.csv` to fetch external data. The SVG output is generated with a custom render function that computes angles via `d3.pie` and positions labels using arc centroids.