Apple says 74% of iPhones launched in the last four years and 66% of all iPhones are running iOS 26; 68% of iPhones were running iOS 18 as of Jan. 21, 2025
Apple has shared updated iOS 26 and iPadOS 26 adoption figures, revealing how many iPhones and iPads are running those software versions.
Context & Ripple Effects
This disclosure supplies Apple’s official installed-base measure after third-party tracking had put January adoption near 50% and flagged a slower rollout than iOS 18. The 66% figure narrows the uncertainty around the earlier external adoption estimates while preserving the comparison with the prior release cycle.
The four-year iPhone cohort is further ahead than the full installed base, showing that version reach differs materially by device age. A later Apple update reported further gains to 79% of all iPhones, indicating that adoption continued to build after this snapshot.
First-order effects
- Developers now have an Apple-reported basis to treat iOS 26 as the majority platform across iPhones, while retaining support and testing for the roughly one-third still on earlier software.
- Apple can point to stronger adoption among recently launched iPhones—74%—than across its full device base, making hardware-age segmentation central to its platform messaging.
Second-order effects
- App publishers and service providers face a clearer trade-off: adopt iOS 26-specific capabilities sooner for most users, or delay requirements to avoid excluding a substantial older-version audience.
- The gap between recent-device and overall adoption makes compatibility decisions more dependent on a product’s customer device mix rather than a single platform-wide adoption threshold.
Third-order effects
- If slower early uptake relative to iOS 18 persists, iOS feature rollouts may become more gradual across the installed base, extending the period in which developers must support multiple OS generations.
- Official platform disclosures become more consequential when third-party measurements diverge, concentrating Apple’s influence over the adoption benchmark used by developers and investors.
The trend: Mobile platform rollouts are becoming more segmented by device age and update behavior, increasing the value of compatibility strategies built around installed-base cohorts.