# DuoBoard: Tutor Whiteboard — Two-screen PDF lesson board

> Two-screen PDF lesson board (iPhone/iPad app by Woosoo Kim.)

- Source: https://appshunter.io/ios/app/duoboard-tutor-whiteboard/id6795011991 (this page in markdown: same URL + `.md`)
- Developer: [Woosoo Kim](https://appshunter.io/developer/6795011993)
- Category: Education, Utilities
- Price: Free with in-app purchases
- Age rating: 4+
- Requires: iOS 17.0 · 3 MB
- Languages: American English, Korean
- Released: 2026-08-05
- Data updated: 2026-11-11

## What is DuoBoard?

Put your PDF workbook on the iPad and send a separate student view to the classroom TV. You see the answers and your notes; students see only what you choose to reveal.

WRITE THE ANSWERS BEFORE CLASS
Write answers with Hidden Ink. They show on your iPad but never on the TV. During class, rub over one with your finger and only that spot appears on the student screen.

TWO SCREENS THAT MOVE SEPARATELY
· Freeze — hold the student screen while you prepare the next question.
· Screen off — blank the TV for a moment when you need attention.
· Peek at the answer key — one tap there and back; the freeze is handled for you.
· TV zoom — keep your own view as it is and enlarge only what the TV shows.
· Cover — hide a spot you are not ready to show.

FOR ENGLISH AND READING CLASSES
· Reading band — dim the TV except the line you are reading.
· Grammar stamps — S, V, O, C, M, relative pronouns and more, 60+ in one tap.
· Syntax tools — brackets, chunking slashes, modifier arrows, numbering.
· Lesson cards — write a grammar note once and stick it on any book.

CLASS FLOW
Lesson timer, laser pointer, scratch board, half-page split for wide books, book tabs, pen presets.

FREE
Two books open at once (workbook + answer key), pen, highlighter, straight line, typing, eraser, hidden ink and rub-to-reveal, cover, freeze, screen off, TV zoom, reading band, timer, laser, scratch board, 60+ built-in stamps.

ONE-TIME UNLOCK (not a subscription)
Unlimited open books, post-it library across books, custom stamps and stamp sets, saved pen presets. Restores on a new device. If you bought the app before 1.4, everything is unlocked automatically.

YOU WILL NEED
An iPad and an external display (HDMI adapter or AirPlay / Apple TV). Apple Pencil recommended.

No purchase prompt ever appears during a class.

## Pricing and in-app purchases

Base price: Free.

**One-time purchases**

| Purchase | Price | Type |
| --- | --- | --- |
| DuoBoard Pro | $6.99 | one-time |


## Is DuoBoard safe?

Not enough ratings yet to assess DuoBoard.

## Is DuoBoard legit?

DuoBoard: Tutor Whiteboard appears legitimate, with a few gaps. The AppsHunter Legitimacy Score for DuoBoard is 65 out of 100 points across 7 verification signals from App Store and developer data.


## Version history (last 5 releases)

### 1.4 — 2026-09-26

DuoBoard is now free. Download it and use it in your next class.

· Two books open at once, free (workbook + answer key)
· Reading band — dim the TV except the line you are reading
· 60+ grammar stamps and syntax tools (brackets, slashes, arrows)
· Pen preset dock on the left edge
· Lesson timer
· Lesson cards (post-its) are quicker to make and move

Fixed
· Ink drifting away from the page on the TV while zooming
· Black bars on the sides of the TV picture
· Typed text not landing on a real device
· Highlighter covering the printed text (now lighter)

If you bought the app before 1.4, every feature unlocks automatically.

### 1.3 — 2026-08-19

• Typing is now reliable — a text box no longer closes when the keyboard appears.
• Swipe to turn pages even while the typing tool is selected.
• Softer highlighter so the text underneath shows through clearly.
• Sticky notes can now use much smaller text, down to worksheet size.
• Fixed leftover ink from the previous page when turning pages.

### 1.2 — 2026-08-17

• Broader undo — pen, text, answer covers/reveals, scratch-to-reveal, and sticky-note create/delete all undo in one tap.
• Tap to place an answer cover instantly, with a smaller default size.
• Delete a cover anytime by long-pressing it—even while the cover tool is on.
• Zoom up to 6× to focus on one column of bilingual worksheets.
• Improved VoiceOver accessibility labels.
• Stability improvements.

### 1.1 — 2026-08-05

DuoBoard is now available in English (US). The same two-screen teaching, fully localized.

### 1.0 — 2026-07-31

No release notes.

## More apps by Woosoo Kim

- [Noeul ON: Sunset Forecast](https://appshunter.io/ios/app/noeul-on-sunset-forecast/id6795621715)
- [HaruOn: Dog Walk & Step Diary](https://appshunter.io/ios/app/haruon-dog-walk-and-step-diary/id6798399661)
- [Chord ON: Guitar Chords, Tuner](https://appshunter.io/ios/app/chord-on-guitar-chords-tuner/id6798905435)
- [Sundle: Golden Hour Planner](https://appshunter.io/ios/app/sundle-golden-hour-planner/id6801230825)
- [무디카 - 차계부 정비 기록 영수증](https://appshunter.io/ios/app/id6802301876)

All apps by Woosoo Kim: https://appshunter.io/developer/6795011993

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-11-11.*