iPhone Air’s C1X Chip Performs on Par With Qualcomm's Flagship X80 Modem, Ookla Says

Apple introduced its new C1X network chip in September last year with the thin and light iPhone Air. Launched earlier this month, the iPhone 17e is also equipped with the same modem. Recently, a report highlighted that the C1X chip failed on a user's iPhone Air when the handset suddenly stopped receiving network signals one morning, which raised doubts about its reliability. However, a report collating network test results from various devices suggests that the Apple Silicon C1X network chip managed to achieve “real-world” performance parity with its competition, which is also found on flagship iPhone models. The new thin and light iPhone model is reportedly also seeing a higher adoption rate than the Plus models.

iPhone Air's C1X Chip Outpaced Qualcomm's Modem on Some Tests

According to a report by Ookla, the Seattle-based network intelligence and diagnosis firm, Apple's proprietary C1X network chip found on the iPhone Air and iPhone 17e has managed to achieve “real-world” parity in latency and download performance with the Qualcomm X80 modem, found on flagship Android phones and iPhone models, including the iPhone 17 Pro Max.

Apple's in-house modem was able to provide similar performance on various networks “in both ideal and challenging conditions”. The report added that Apple's C1X network chip is no longer a compromise over the competition from the chipmaker Qualcomm. Instead, the C1X chip has come out as a “performance equaliser”. However, the report also acknowledged that the upcoming flagship Android phones, scheduled to be launched in the first half of this year, will be equipped with the Qualcomm X85 modem, which is expected to ship with enhanced performance over its predecessor.

Interestingly, Ookla also highlighted that the iPhone Air outpaced the iPhone 17 Pro Max, which uses the Qualcomm X80 chip, in terms of latency. The C1X-equipped iPhone Air managed to outperform the flagship iPhone model on various latency metrics in 19 of 22 markets, based on the speed test data analysed. The report speculates that this could have been possible because of Apple's better modem-to-processor integration, emerging as a “key differentiating point” for the Apple Silicon-powered devices.

However, Apple's proprietary chip reportedly still struggles in some aspects. For example, the Qualcomm X80-equipped iPhone 17 Pro Max retained up to a 32 percent lead in upload speeds. This reportedly suggests that the C1X modem could be limited by its narrower carrier aggregation capability. The report also highlighted that Qualcomm X80's superior upload speed performance is due to the Uplink Carrier Aggregation (UL-CA), which “remains the industry benchmark”.

Ookla's speed test results also indicate that the new iPhone Air, which was launched in September 2025 along with the iPhone 17 series, is seeing a higher adoption rate than the Plus models, with South Korea being the largest market for the thin and light handset, followed by Japan, Sweden, Singapore, Italy, Spain, and UAE.