C1 Modem On IPhone 17 Air Still Losing Fast In Several Operators

JAKARTA - Apple continues to seek to break its dependence on the Qualcomm modem by developing its own modem. Apple's first modem chip, C1, was first used on the iPhone 16e and is expected to be also present on the iPhone 17 Air. However, recent research from Ookla reveals that C1 performance has not been fully able to compete with Qualcomm modem, especially in several major operators.

Ookla, the company behind the Speedtest.net service, analyzes millions of internet speed data from around the world to compare the performance of the iPhone 16 which uses Qualcomm modem with the iPhone 16e which uses Apple C1 modem. The results show a mixed picture.

The first report in March indicated that C1 excels in areas with a weak signal, keeping connections stable. However, Qualcomm modem is still superior in areas with the fastest 5G connection. The latest report from Ookla reiterated this discrepancy, while highlighting that performance is also heavily influenced by the operator used.

For example, the carrier aggregation feature technology that combines several frequencies to increase speed supports four channels on the Qualcomm modem, but only three on the C1 modem. The impact is quite significant on the US T-Mobile network.

According to Ookla, the iPhone 16 on the T-Mobile network is capable of reaching a median download speed of 317.64 Mbps, while the iPhone 16e with a C1 modem only records 252.80 Mbps. RootMetrics controlled tests during the first half of 2025 also found that T-Mobile used four-channel aggregation in 65.4% of locations, giving the device a clear advantage with a Qualcomm modem.

Globally, the iPhone 16 is shown to be faster than 16e in countries with the most advanced 5G networks like China and Saudi Arabia. However, in most other countries, both offer nearly equivalent speeds. Interestingly, the modem C1 is actually better at maintaining connections in areas where signals are weak, suggesting that Apple may prioritize connection reliability over peak speeds.

For prospective iPhone 17 Air buyers, this result can be taken into consideration. You will get a more stable connection in a signal-tightened area, but may be a little behind in areas with the fastest networks, especially if you use operators that already support the aggregation of four channels such as T-Mobile.