The iPhone 17 Ultra is not specifically mentioned in the available information, but the iPhone 17 Air is noted to use Apple's C1 modem. Assuming similar technology might be applied across the lineup, here's how the C1 modem could impact connectivity:
Overview of the C1 Modem
The C1 modem is Apple's first custom-designed modem chip, marking a significant step towards reducing reliance on external suppliers like Qualcomm. It is highlighted for its power efficiency, which contributes to better battery life, even in ultra-thin devices like the iPhone 17 Air[1][4][9].
Connectivity Features
- 5G Support: The C1 modem supports sub-6GHz 5G networks but lacks support for mmWave 5G technology. This means users will not have access to the ultra-fast speeds mmWave offers in specific locations such as stadiums, airports, and dense urban areas[1][4][6].
- Theoretical Speeds: The C1 modem is capable of theoretical download speeds of up to 4 Gbps, which is slower than Qualcomm's modems used in other iPhone models[5][6].
- Efficiency and Battery Life: The power efficiency of the C1 modem helps improve battery life, making it suitable for devices with smaller form factors[9].
Impact on Connectivity
The absence of mmWave support means that devices using the C1 modem, like the iPhone 17 Air, will rely on sub-6GHz networks for 5G connectivity. While these networks provide broader coverage, they offer slower peak speeds compared to mmWave. This could impact users who frequently need high-speed data in areas where mmWave is available[1][4].
However, for most users, the sub-6GHz coverage will suffice, and the improved battery life due to the modem's efficiency will be a significant advantage. Apple is already working on a second-generation modem that will include mmWave support, expected to debut in the iPhone 18 lineup[1][7].
Other Connectivity Improvements
While the C1 modem focuses on cellular connectivity, Apple is also enhancing Wi-Fi capabilities across the iPhone 17 series with custom Wi-Fi 7 chips. These chips promise faster speeds and improved efficiency, enhancing overall wireless performance[2][5].
In summary, the C1 modem in the iPhone 17 Air (and potentially similar models) offers efficient battery management and reliable sub-6GHz 5G connectivity but lacks the ultra-fast speeds of mmWave technology. This setup is part of Apple's broader strategy to control its wireless stack and improve device efficiency.
Citations:
[1] https://www.macrumors.com/2025/02/20/iphone-17-air-we-now-know-everything-this-feature/
[2] https://www.geeky-gadgets.com/iphone-17-lineup-leaks-5-new-updates-you-need-to-know/
[3] https://appleinsider.com/articles/25/02/20/iphone-17-may-not-get-apples-c1-modem-but-will-get-a-new-wi-fi-chip
[4] https://www.macrumors.com/2025/02/20/apples-c1-modem-iphone-17-air-lack-mmwave/
[5] https://www.macrumors.com/roundup/iphone-17/
[6] https://www.macworld.com/article/2618003/apple-iphone-c1-5g-modem-faq.html
[7] https://www.phonearena.com/news/fresh-report-says-most-iphone-17-models-to-use-mediatek-5g-modem_id167872
[8] https://www.youtube.com/watch?v=dSiEAcB-xIM
[9] https://9to5mac.com/2025/02/25/apples-new-c1-brings-two-killer-features-and-its-just-the-start/
[10] https://www.forbes.com/sites/davidphelan/2025/03/11/apple-iphone-17-pro-max-design-new-leak-hints-at-major-upgrade/