Duo app icon

Apps Like Duo for iPhone and iPad

Test responsive web design views simultaneously.

The app displays a desktop and mobile view simultaneously for responsive web design testing. Users can navigate both panes with synchronized browsing and access WebKit Dev Tools for debugging.

by Electric Pulp★ 0.00 ratingsDeveloper Tools$4.99Data updated 2026-10-25
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Ranked alternatives

Showing 301–320 of 1,000 ranked alternatives.

  1. Graffito app icon

    Graffito

    Jonathan Knopf

    Draw, shape, and view 3D graffiti

    Create digital graffiti signatures and throw-ups with fluid line drawing and responsive smoothing. Generate 3D models from strokes for interactive viewing. Export in USDZ or SCN formats for sharing or AR preview.

    ★ 5.01 ratingsGraphics & DesignFreeData updated 2026-09-06
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  4. Hard Refresh app icon

    Hard Refresh

    Albuquerque de Matos, Unipessoal, LDA

    ★ 0.00 ratingsDeveloper Tools$1.99Data updated 2026-11-11
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  7. Web Sync app icon

    Web Sync

    Erfan Reed

    Render web pages on dual displays

    Display web pages on both device and external screen simultaneously. Control content on each screen independently. Mirror or split views via HDMI, AirPlay, or AV adapter. Manage web content remotely from any location.

    ★ 5.01 ratingsDeveloper ToolsFreeData updated 2026-09-06
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  8. MarkNote - Markdown Note app icon

    MarkNote - Markdown Note

    淑敏 孙

    Take notes, sync, and share documents

    Take notes using with syntax highlighting and code snippet support. Embed photos, images, and mathematical formulas. Sync notes across iOS and macOS devices via iCloud. Send formatted emails and share notes with others.

    ★ 4.85 ratingsProductivity$1.99Data updated 2026-09-09
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  11. Smart HTML Editor with AI app icon

    Smart HTML Editor with AI

    Merbin Joe

    Code, preview, share projects

    Allows users to write, edit, and preview , CSS, and JavaScript code. Features include AI-powered code generation, snippet explanations, and real-time preview. Users can save projects, share code, and access offline functionality.

    ★ 4.02 ratingsEducationFreeData updated 2026-09-22
    App details
  14. QuackBASIC: Code in BASIC app icon

    QuackBASIC: Code in BASIC

    Ammonite Design Studios Ltd

    In , run programs, relive programming history

    Write and execute on mobile devices. Debug programs in real-time. Access a library of sample and tutorials. Save and share projects. Integrate with cloud storage for backups. Run legacy programs and explore retro programming features.

    ★ 4.25 ratingsDeveloper ToolsFreeData updated 2026-09-06
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  15. Xcasca app icon

    Xcasca

    NetSarang, Inc.

    ★ 1.06 ratingsDeveloper ToolsFreeData updated 2026-09-06
    App details
  17. U Game Engine + xLua app icon

    U Game Engine + xLua

    盼军 崔

    Create games in 2D and 3D

    Create and run 2D and 3D games directly on iOS. Script gameplay using Lua for lightweight, fast development. Test changes in real time with instant feedback. Import assets and build interactive projects without needing a computer.

    ★ 5.01 ratingsDeveloper Tools$19.99Data updated 2026-09-06
    App details

How we rank alternatives

Apps are ranked by functional similarity, category fit, rating confidence, and popularity.