DuoCalc – Calculator & Notes

Calculator with scratch paper

Only for iPhone

$0.99 · Designed for iPhone. Not verified for macOS.

iPhone

Designed for iPhone Duo. Fold it closed for a clean calculator; open it up to calculate on one side and jot, circle and annotate on scratch paper on the other. DuoCalc is a calculator with a scratch pad built in — designed for the foldable iPhone Duo and great on every iPhone. Folded, it's a clean, easy-to-tap calculator. Unfolded, the calculator sits on one side and a sheet of scratch paper on the other, so you can keep intermediate results, list steps and sketch ideas without switching apps. • Results to paper in one tap: tap the arrow to place a result on the paper, or touch and hold to send or drag the whole expression • Handwriting on top: write with your finger or Apple Pencil in three colors — your ink sits above the numbers, perfect for circling and annotating • Layouts for every pose: folded, unfolded, portrait and landscape each get a dedicated layout • Keep it or toss it: pages are thrown away by default; save the ones you want with one tap, or turn on auto-save • Calculation tape: every calculation is kept — tap one to bring the result back • Accurate math: decimal arithmetic, so 0.1 + 0.2 = 0.3 • Quiet and private: no ads, no account, no internet — your data stays on your device

A Closer Look

Ratings & Reviews

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• English and Traditional Chinese • Small improvements

Version 1.1

The developer, 浩然 林, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .

  • Data Not Collected

    The developer does not collect any data from this app.

    Privacy practices may vary, for example, based on the features you use or your age. Learn More

    Accessibility

    The developer has not yet indicated which accessibility features this app supports. Learn More

    Information

    Seller
    浩然 林
    Size
    911.4 KB
    Category
    Utilities
    Compatibility
    Requires iOS 17.0 or later.
    • iPhone
      Requires iOS 17.0 or later.
    • Mac
      Requires macOS 14.0 or later and a Mac with Apple M1 chip or later.
    Languages
    English and 2 more
    • English, Simplified Chinese, Traditional Chinese
    Age Rating
    4+
    Copyright
    © 2026 HaoRan Lin
  • Privacy Policy

    • Supports

    • Family Sharing

      Up to six family members can use this app with Family Sharing enabled.