Apple's C1 Modem vs Qualcomm: Early Performance Results Show Promise and Limitations

Updated: March 20 2025 10:05
When Apple announced it would be designing its own cellular modems, the tech world took notice. After years of relying on Qualcomm's technology, Apple's first in-house modem—the C1—has finally made its debut in the iPhone 16e released in February. This represents a significant milestone in Apple's vertical integration strategy, but the critical question remains: how does it actually perform?


Thanks to Ookla's Speedtest Intelligence data collected during the first two weeks of March 2025, we now have our first real-world performance metrics. The results paint an interesting picture of Apple's first-generation modem technology, with some surprising strengths and expected limitations.


One of the most interesting findings from Ookla's analysis is that the C1 modem seems to prioritize consistent performance over peak speeds. When comparing the iPhone 16e (with the C1 modem) against the standard iPhone 16 (with Qualcomm's modem), the data shows the 16e performs better for users experiencing the poorest connections.


Users in the bottom 10th percentile—those with the weakest signals or most congested networks—saw significantly better download speeds with the iPhone 16e across all three major US carriers:

• AT&T: 31.16 Mbps on 16e vs. 10.80 Mbps on 16
• T-Mobile: 57.34 Mbps on 16e vs. 27.27 Mbps on 16
• Verizon: 23.01 Mbps on 16e vs. 15.91 Mbps on 16

However, the story changes completely when examining the top performers. For users with excellent connectivity (the 90th percentile), the iPhone 16 with Qualcomm's modem achieved substantially higher download speeds:

• AT&T: 634.13 Mbps on 16 vs. 544.61 Mbps on 16e
• T-Mobile: 889.83 Mbps on 16 vs. 627.01 Mbps on 16
• Verizon: 660.59 Mbps on 16 vs. 496.03 Mbps on 16

This pattern suggests Apple may have deliberately optimized the C1 modem to improve the experience for average users rather than chasing benchmark-topping speeds that few would regularly experience.



Perhaps the most revealing aspect of the data is how differently the C1 modem performs across the three major US carriers. For median download speeds, the iPhone 16e outperformed the iPhone 16 on AT&T and Verizon but significantly underperformed on T-Mobile:

• AT&T: 226.90 Mbps on 16e vs. 146.49 Mbps on 16 (55% improvement)
• Verizon: 140.77 Mbps on 16e vs. 124.40 Mbps on 16 (13% improvement)
• T-Mobile: 264.71 Mbps on 16e vs. 357.47 Mbps on 16 (26% decrease)

This T-Mobile anomaly likely stems from the carrier's nationwide 5G standalone (SA) network with advanced features like carrier aggregation. According to Ookla's analysis, the C1 modem appears to have more limited capabilities on these advanced networks compared to Qualcomm's solution.

Interestingly, the C1 modem shows consistent improvements in upload speeds across all carriers:

• AT&T: 14.63 Mbps on 16e vs. 8.60 Mbps on 16 (70% improvement)
• T-Mobile: 14.91 Mbps on 16e vs. 14.15 Mbps on 16 (5% improvement)
• Verizon: 13.24 Mbps on 16e vs. 8.72 Mbps on 16 (52% improvement)

This is a notable achievement for Apple's first modem design, especially considering how crucial upload performance is becoming for social media sharing, video calls, and cloud backups.


While Apple's C1 modem shows promise, it does come with some notable technical limitations compared to Qualcomm's offerings:

• No mmWave support (a first for US iPhones)
• Limited to 3x downlink carrier aggregation (compared to 4-6x on Qualcomm modems)
• No support for uplink carrier aggregation
• No support for uplink MIMO
• WiFi 6 support instead of WiFi 7 (which is available on other iPhone 16 models)

These limitations explain some of the performance differences observed in the data, particularly the lower peak speeds and the poorer performance on T-Mobile's advanced network.


Apple has emphasized that the C1 modem is designed for power efficiency, and this appears to be reflected in the iPhone 16e's battery specifications. Apple claims the 16e offers up to 26 hours of video playback (vs. 22 hours on iPhone 16), and up to 21 hours of streaming video playback (vs. 18 hours on iPhone 16).

The company has also mentioned that the 16e features a new internal design allowing for a larger battery, which contributes to this improvement. According to independent testing, the C1 modem is up to 25% more power-efficient than Qualcomm modems used in previous iPhones, giving credence to Apple's claims.


Just as Apple is taking its first steps into modem design, Qualcomm is pushing the boundaries even further with its next-generation X85 modem, announced at Mobile World Congress 2025 in Barcelona this March.


Qualcomm CEO Cristiano Amon didn't mince words when speaking to CNBC about the performance gap between their latest technology and Apple's first effort. Amon claimed the X85 would create a huge delta in performance between premium Android devices and Apple's iPhones. The X85 certainly impresses on paper with specifications that far exceed Apple's C1:

• 5G mmWave support (which the C1 lacks entirely)
• 400MHz download bandwidth in the Sub-6GHz spectrum with 1024-QAM modulation
• Satellite connectivity
• Peak download speeds of up to 12.5Gbps
• Peak upload speeds of up to 3.7Gbps

Perhaps most notably, Amon emphasized the X85's AI-powered capabilities: "It's the first modem that has so much AI, it actually increases the range of performance so the modem can deal with weaker signals," he told CNBC.


This is particularly interesting given that our Ookla data shows the C1 modem already performs better with weaker signals compared to previous Qualcomm modems—suggesting that Apple and Qualcomm are both prioritizing consistent connectivity but taking different approaches to achieve it.


While Apple's first-generation C1 modem is now in consumers' hands with the iPhone 16e, those hoping for rapid improvements—particularly the addition of mmWave support—may need to temper their expectations. According to a new report from respected analyst Ming-Chi Kuo, an updated version of the Apple C1 modem with mmWave support won't enter mass production until 2026.

Apple's C1 modem process technology:
- Baseband: 4/5nm (both technologies are similar)
- Low-frequency/Sub-6 TRx (Transceivers): 7nm
- Intermediate Frequency (IF) TRx: 7nm
- PMIC: 55nm

The C1 refreshed version is under development for mass production next year, aiming to improve…

— 郭明錤 (Ming-Chi Kuo) (@mingchikuo) March 6, 2025

This timing suggests that even the iPhone 17 lineup, expected in late 2025, will likely not feature an mmWave-capable Apple modem. Instead, the premium iPhone 17 models will probably continue to use Qualcomm modems for at least one more generation.

Kuo also shared some interesting details about Apple's modem manufacturing strategy. The "refreshed C1" chip is likely to be built using a 28nm process rather than the 3nm process used for Apple's latest A-series processors. "Unlike processors/GPUs, baseband chips don't aggressively adopt the latest advanced node because the return on investment isn't high," Kuo explained. "As a result, it's unlikely that Apple's baseband will shift to a 3nm process next year."

This manufacturing approach makes sense when considering that modems prioritize power efficiency over raw computational power, and the latest fabrication processes aren't always necessary to achieve significant improvements in modem technology.


Despite Apple's move to develop its own modem technology, the company isn't cutting ties with Qualcomm just yet. Apple's current agreement with Qualcomm extends through 2026, allowing Apple time to refine its modem technology while still using Qualcomm's hardware in premium iPhone models.

However, Amon has reaffirmed his expectation that Qualcomm will stop supplying Apple with modems by 2027. He also underscored the growing importance of modems in AI-powered devices: "In the age of AI, modems are going to be more important than they have ever been. And I think that's going to drive consumer preference about whether they want the best possible modem in the computer that's in their hand all the time."

The X85 modem is expected to debut later this year in the Snapdragon 8 Elite Gen 2, launching in October 2025, while Apple's current C1 modem is reportedly set to appear in the upcoming iPhone 17 Air as well, according to Kuo.


As Apple's first attempt at designing its own cellular modem, the C1 shows both promise and room for improvement. The focus on consistent performance for users with weaker connections rather than headline-grabbing peak speeds seems to be a deliberate strategy—and arguably one that benefits more users in real-world scenarios.

The missing mmWave support and other advanced features are likely to be addressed in future iterations, though it appears this will happen more slowly than some might have expected. Remember that Apple's A-series processors weren't class-leading in their first generations either, but they've since become industry benchmarks. We can probably expect a similar trajectory for Apple's modem technology, albeit potentially with a longer timeline.

With Qualcomm already touting significant advantages with its X85 modem and mmWave support for Apple's in-house modems delayed until 2026, Apple clearly has its work cut out to close the technological gap before Qualcomm potentially stops supplying modems to Apple around 2027. This gives Apple approximately one to two years to refine its modem technology to competitive levels once the mmWave-capable version enters production.

For now, the iPhone 16e represents an interesting option for users who prioritize battery life and reliable connectivity over bleeding-edge speeds and the very latest wireless technologies. And if Apple's track record with its other in-house silicon is any indication, we can expect steady improvement in future generations of its modem technology, even if that improvement comes at a more deliberate pace than Apple's processor advancements.