Ookla’s C1X report’s most shocking result? People are buying iPhone Air

Macworld Cellular research and analysis company Ookla, owners of the very popular Speedtest app and site, has issued a fascinating report gleaned from Speedtest user data in the fourth quarter of 2025. There are two key takeaways: The iPhone Air is more popular than other premium “slim” phone variants and the iPhone “Plus” models it replaced, and Apple’s C1X modem has made enough improvements over the C1 to be a fully “tier 1” modem, offering an overall equal alternative to Qualcomm’s X80 in most respects. iPhone Air sales While Apple’s C1X debuted in the iPhone Air, it has since appeared in a few iPads and now the iPhone 17e. Ookla’s data is from the 4th quarter of 2025 and focuses on smartphones, though. So all C1X results in this report are exclusively iPhone Air results. While Ookla doesn’t have sales data, it collects speed results and hardware identifiers from millions of users, so it is generally true that the ratio of Speedtest results mo