OneDrive: PDF annotation for sensitivity-label protected PDFs in the OneDrive apps (iOS and Android)

The Microsoft OneDrive apps for iOS and Android will let users annotate PDFs protected by a Microsoft Purview Information Protection sensitivity label that applies encryption — without removing or weakening the label. Users with edit/annotate rights can add a full set of annotations — including ink, highlight, free text, notes, signatures, image/shape/date stamps, bookmarks, and form fields — directly in the OneDrive mobile PDF viewer; the file's encryption and usage rights are preserved end to end. This applies to the OneDrive apps for iOS and Android only (not OneDrive or SharePoint on the web). The feature is enabled by default for eligible users and requires no new admin action.