Microsoft has warned in the release notes for OneDrive 18.11.2 that it plans to end support for iOS 18 and iPadOS 18 soon. The company recommends moving to iOS or iPadOS 26 or 27 to keep receiving the latest versions of the app.
The biggest impact will be on hardware that cannot install iOS/iPadOS 26. Apple's compatibility lists start with the iPhone 11 and the 8th-generation iPad, leaving the iPhone XR, iPhone XS, iPhone XS Max and 7th-generation iPad on the older operating system. Newer devices that are still on iOS 18 can avoid the issue by installing a supported newer system version.
The change has not taken effect yet: the current public OneDrive listing still names iOS 18.0 and iPadOS 18.0 as the minimum requirements, and Microsoft has not provided an exact cutoff date. Once the minimum requirement increases, an existing installation is unlikely to stop working immediately, but affected devices will no longer receive new features, bug fixes or app security updates. Users of older hardware should therefore confirm that important files are fully synced and plan how they will access their data from a supported device.