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Agora Flat provides web and desktop clients for creating, joining, and scheduling online classrooms. Teachers and participants can combine an interactive whiteboard with live audio, video, messaging, screen sharing, and course materials, then replay recorded classroom activity. The open-source client may be used commercially, but the project does not provide commercial customization, deployment assistance, or customer support.

Thorium Reader is a desktop EPUB reader for Windows, macOS, and Linux. It imports books from local directories or OPDS feeds, then lets readers adjust layouts, navigate by table of contents or page list, and save bookmarks, with explicit attention to screen-reader accessibility. Builds made only from the public source support the basic LCP encryption profile; broader production-grade LCP support requires an additional component.

Piano Trainer turns scales, chords, and the circle of fifths into interactive desktop exercises. Learners can respond with a MIDI keyboard or the computer keyboard, then reinforce recall through quizzes, hard mode, and shuffled practice. Free cross-platform builds are available. It works best as a hands-on reference and repetition tool for self-paced learners rather than as a complete structured piano course.

MarkerOn lives in the system tray and opens a screen-wide annotation layer with a global shortcut. Draw, highlight, add arrows, shapes, or text, then enable click-through mode to keep the marks visible while interacting with the application underneath. It also includes a whiteboard, image copying, and optional drawing persistence. The roughly 1.5 MB desktop app supports Windows, macOS, and Linux.