Detailed Apple C1 test results show carriers are the problem

At the end of February, Apple made a bit of history by releasing its first product to use its a cellular chip of its own design. The Apple C1 is a 5G-capable modem that lacks some of the most advanced features (like mmWave support) and should be, on paper, not quite as good as the Qualcomm-made modem in the regular iPhone 16 line. Apple’s focus appears to be on reliability and power efficiency with the C1, with analysts expecting Apple to catch up on performance with the next-generation C2 modem.

In our own limited testing, we found the iPhone 16e to be quite a bit slower than the iPhone 16 in several locations around on metropolitan area on one network, but that only tells part of the story.

Ookla, which creates the popular Speedtest app, published results from user-run tests during the first 12 days of availability in the United States and found that the iPhone 16 had higher overall speeds, but that the iPhone 16e could hold its own or even come out ahead depending on network, location, and network conditions.

Now, with months of data collected from millions of Speedtest users all over the world, Ookla has published far more comprehensive results.

The key takeaway is this: Qualcomm’s modem does better on networks that are more advanced and higher-performance, while Apple’s C1 modem performs better under very specific circumstances.

Qualcomm’s superior average download performance is highly network dependent, and even in its best regions (Saudi Arabia and China) is only about 20 percent faster than the C1 on average. On the other hand, Apple’s C1 pulls ahead on tests below the 10th percentile (the 10% of tests with the slowest results). Those tests are likely on low-band 5G connections and don’t make use of high levels of carrier aggregation, where Qualcomm shines.

Ookla

Upload performance is quite good on Apple’s modem in the iPhone 16e, compared to Qualcomm’s modem in the iPhone 16. Apple’s modem delivered higher median upload speeds in 15 of the 21 markets examined by Ookla, and while the difference was often slight, it’s fair to say the C1 has better overall median upload performance.

Ookla

Of course, Ookla’s tests are just examining the iPhone 16e (the only phone with Apple’s C1 modem) against the iPhone 16. The Qualcomm modem in the iPhone 16 is the Snapdragon X71M, a custom variant made for Apple but based on designs that are a couple of years old now. The Snapdragon X80 and X85 are Qualcomm’s newest high-end modems and are found in most Android flagship phones. When we say the C1 compares favorably against Qualcomm in these tests, we’re not comparing against Qualcomm’s best.

Apple is expected to use Qualcomm modems once again in most of the iPhone 17 line set to debut on September 9, but the ultra-slim iPhone 17 Air is rumored to use the C1 modem.