Comparison

TextbookDojo vs Red Sheet

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

TextbookDojo

Features
Read full description

TextbookDojo is an app for "Memorization sheet". The "Memorization sheet" is a Japanese style memorization method. TextbookDojo means "memorize everything" in Japanese. With this method, you first hide the strings you want to remember from a textbook or notebook, and later see repeatedly if you have remembered them. This app turns memorization sheets into flashcards. Recommended for students studying medicine, law, geography, foreign languages, economics, programming, etc. These are fields that require a lot of memorization. # Main Features - Memorize textbooks and problem books by hiding the parts you want to remember. - Automatic AI-based Important Phrase Marking Feature - Supports memorization of question collections with questions and answers separated from each other - Voice recording and playback function - Free drawing function - By automatically alternating playback of questions and answers, memorization can be done without manipulating the flashcards. - Intensive memorization of weak points. - By adjusting the playback speed of the flashcards, you can memorize them at high speed. - Test questions based on the forgetting curve allow you to concentrate on memorizing the questions you have difficulty with. - An automatic zoom function allows non-stress memorization even for those who have difficulty with small letters or presbyopia. - Pages can be imported from PDF/photo/camera. - You can share books and markers with your friends. - You can create an unlimited number of books, pages, and markers for free. === Other details === # Premium Features - In the free version, ads are displayed during memorization. In the Premium version, no ads are displayed. # About Premium The Premium version has no advertisements and no functional limitations. Premium monthly fee: $4.49 Premium yearly fee: $32.99 *It will automatically renew within 24 hours before the end of the term. - Payment Method Payment is charged to your iTunes account. - Cancel Auto-Renewal Auto renewal billing settings must be cancelled at least 24 hours prior to the end of the one-month or one-year subscription period. Cancellation during the period is not allowed. Auto-renewal billing will be done at least 24 hours prior to the end of the term. - How to cancel auto-renewal 1. open the "Settings" application. 2. tap your name. 3. tap "Subscribe". 4. your iPhone will display the "Subscriptions" menu option in "Settings". 5. tap the subscription you wish to manage. 6. tap Cancel Subscription. - Restore when changing devices If you change devices, you can restore your previously purchased paid version for free; just sign in again with the account you used with TextbookDojo. Privacy Policy https://www.fukurobo.com/others-en.html#privacy Terms of Use https://www.fukurobo.com/others-en.html#legalnotice

About

Red Sheet

Create and study flashcards from your PDFs, notes, and images. This app lets you hide and reveal text to transform study materials into interactive flashcards for faster memorization. Supports various import options and flexible study tools.

Highlights
  • Create flashcards from PDFs
  • Import from note apps and cloud storage
  • Hide and reveal text for study
  • Create flashcards from photos and images
  • Vocabulary and word list flashcards
  • One-tap show/hide for quick review
Features
Read full description

◆ All-in-One PDF Memorization App with Red Sheet Study Turn your PDFs, notes, textbooks, handouts, and images into powerful study materials. This app helps students memorize faster by hiding and revealing important parts of their own documents. Import PDF files, photos, scanned notes, class handouts, worksheets, and study materials, then create memorization blocks directly on the page. It works like a digital red sheet, flashcard maker, and PDF study tool in one simple app. ◆ PDF Memorization Made Simple ・Import PDF files and study directly from the page ・Hide words, definitions, formulas, diagrams, and answers ・Tap to reveal hidden areas while reviewing ・Use red sheet style memorization on PDF pages ・Study textbooks, school handouts, exam materials, and notes ・Create your own PDF memorization notebook If you already study with PDFs, this app turns them into active memorization tools. ◆ Red Sheet Style Study for PDFs and Images Use memorization blocks to cover the parts you want to remember. Place blocks over text, formulas, diagrams, definitions, answers, or explanations. ・Hide text like using a red sheet ・Reveal answers by tapping ・Create blocks anywhere on a PDF or image ・Adjust block size by dragging the edges ・Change the color and style of blocks ・Use blocks for notes, textbooks, worksheets, and scanned documents This is useful when you want to memorize from your own materials without rewriting everything into separate flashcards. ◆ Smooth Vertical Review for Memorization Review multiple PDF pages and images smoothly. Vertical scrolling makes it easy to study long documents, like moving a red sheet from top to bottom. ・Scroll vertically through study pages ・Review many PDF pages at once ・Memorize photos and handouts continuously ・Swipe between pages and cards ・Add more images when needed ・Study at your own pace Useful for test prep, school study, certification exams, language learning, and daily review. ◆ Useful Study Tools ・One-tap show and hide for fast review ・Multiple memorization blocks for one page ・Auto-align blocks for cleaner layouts ・Zoom in with two fingers to study small text ・Hidden areas stay aligned even when zooming ・Add memo text to support memorization ・Hide memo text for self-testing ・Organize study decks by title or subject Create separate study materials for English, science, history, math, medical terms, law, certification exams, or any subject that requires memorization. ◆ Great For ・Students preparing for tests and exams ・PDF study and textbook review ・Vocabulary memorization ・Language learning ・Science, history, math, and social studies ・Certification exam preparation ・Medical, legal, and technical study ・People who want a simple flashcards maker ・Students who use GoodNotes, notes apps, or PDF files ・Anyone who wants to memorize from their own materials ◆ How to Use 1. Import a PDF file, photo, or image 2. Place memorization blocks over the parts you want to hide 3. Tap to reveal the answer while studying 4. Repeat until you can remember it 5. Organize your materials by subject and review again ◆ Why This App Is Different This app focuses on PDF memorization and red sheet style study. You do not need to recreate every page from scratch. Use your own PDFs, notes, handouts, images, and textbooks as they are, then hide only the parts you want to memorize. It is a simple way to turn everyday study materials into flashcard-style memorization tools. ◆ Recommended If You Want ・A PDF study app for memorization ・A flashcards maker from PDFs ・A red sheet style study app ・A way to memorize school notes and handouts ・A simple tool for exam preparation ・A study app that works with your own materials ・A faster way to hide and reveal answers Start studying your own PDFs, notes, and images with red sheet style memorization. Make your study materials easier to review, repeat, and remember. Terms of Service https://hidevoicy.com/en/tos Privacy Policy https://hidevoicy.com/en/privacy

Screenshots

TextbookDojo4 screens
Red Sheet4 screens

Verdict

The call

The clearest difference is update cadence: Red Sheet at every 3 days against TextbookDojo's every 9 days. On price, ads, in-app purchases and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. TextbookDojo sells 3 in-app purchases, starting at $4.49 per month and Red Sheet sells 7 in-app purchases, starting at $2.99 per month. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

TextbookDojo ships an update every 9 days, Red Sheet every 3 days. The most recent releases landed on October 15, 2026 and October 20, 2026 respectively.

Scorecard1 real difference · 9 level
TextbookDojo versus Red Sheet: the parameters behind the verdict, then further details
ParameterTextbookDojoRed Sheet
PriceFreeFree
Rating—4.2 (5 ratings) — better
Positive reviews—77.8% of reviews
Number of ratings—5 — better
Update frequencyEvery 9 daysEvery 3 days — better
AdsYesYes
In-app purchasesYesYes
Monetization—Free with in-app purchases
DevicesiPhone, iPad, iPodiPhone, iPad, iPod, Mac — better
Requires iOS14.013.0 — better
Further details — not scored
Size102 MB193 MB
Age rating4+4+
DeveloperROBOBO, K.K.Foodmenu.world Inc.

In-app purchases

3 purchases

TextbookDojo

Subscriptions3
  • 1 month payment$4.491 Month
  • 1 year payment$19.991 Year
  • プレミアム年払い(期間限定特別価格)$19.991 Year
7 purchases

Red Sheet

Subscriptions7
  • Monthly Special plan$2.991 Month
  • Monthly Super Saver Plan$2.991 Month
  • Monthly Value Plan$3.991 Month
Show 4 more
  • Basic Plan$5.991 Month
  • 3 Month Plan - V 3.1.5 needed$9.993 Months
  • Half year plan (Sale)$17.996 Months
  • Half year plan - V2.9.0 needed$22.996 Months

Questions

Is TextbookDojo free?
TextbookDojo is free to download, with in-app purchases available.
Is Red Sheet free?
Red Sheet is free to download, with in-app purchases available.
Do TextbookDojo or Red Sheet have ads?
Both TextbookDojo and Red Sheet show ads.
Which is updated more often, TextbookDojo or Red Sheet?
TextbookDojo ships an update every 9 days, and Red Sheet every 3 days. Most recently, TextbookDojo was updated on October 15, 2026 and Red Sheet on October 20, 2026.

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