Comparison

THE CURVE vs 記憶KEEPER

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

Head to head
About

THE CURVE

Create custom flashcards for efficient learning based on the forgetting curve. Review challenging material strategically to optimize memory retention for various subjects and exams.

Highlights
  • Create custom flashcards
  • Supports language learning and exam prep
  • Learning modes based on forgetting curve
  • Review challenging cards intensively
  • Track learning levels with progress indicators
Features
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THE CURVE is a flashcards maker app that is not only based on an efficient & effective iterative learning method, but also adheres to the principles of the forgetting curve for optimal learning efficiency! You can learn various things anytime, anywhere. This app supports language learning, exam preparation, regular tests, qualification acquisition, and more! You can add as many words as you want to memorize, so let’s create your own original flashcards. With the learning mode, which is based on the correct answer rate, you can intensively review only those flashcards that you find challenging, ensuring that your study sessions align with the forgetting curve for maximum retention. Features: • You can create flashcards freely. • You can create multiple flashcards for various memorization tasks, studies, and learning objectives. • You can enter notes on both the front and back of the flashcard, which is convenient for including example sentences. • You can easily learn by simply tapping “Correct” or “Incorrect”. • By using the learning mode, you can review in an efficient and effective manner. • The app adheres to the principles of the forgetting curve, optimizing your learning efficiency. Learning Modes: You can choose from various learning modes based on your needs. These modes allow you to focus on specific aspects of your vocabulary. Here are the available options. Feel free to choose the mode that suits your learning style and goals! • Forgetting Curve Mode: Learn words based on the forgetting curve, which optimizes retention by reviewing at the right intervals. • All Flashcards Mode: Study all the cards in your set. • Unlearned Mode: Concentrate on cards you haven’t encountered yet. • Incorrect Answers Mode: Review only the cards you’ve answered incorrectly. • Correct Answers Mode: Reinforce your memory by revisiting cards you’ve answered correctly. • Challenging (Rate 40% or Less) Mode: Target cards with a low accuracy rate. • Challenging (Rate Under 50%) Mode: Focus on cards with moderate difficulty. • Challenging (Rate Under 70%) Mode: Tackle cards that need improvement. Learning and Review Based on the Forgetting Curve: • Leveraging the theory of “Ebbinghaus’ forgetting curve”, this approach prioritizes efficient learning through strategic review. • By repeating reviews at appropriate intervals aligned with the forgetting curve, you can enhance memory retention. • These review results are reflected in your “learning level”, indicating your degree of mastery. • Remember that consistent review, especially when memories are on the verge of fading, contributes significantly to long-term retention. Learning Levels Based on the Forgetting Curve: According to the forgetting curve, if you answer correctly after a certain number of days from your last learning session, your learning level will increase. Learning levels are represented by chess pieces, starting from Level 1 (Pawn). Here’s the breakdown. • Level 1 - Answer correctly after 10 minutes -> Level 2 (Knight) • Level 2 - Answer correctly after 1 day -> Level 3 (Bishop) • Level 3 - Answer correctly after 2 days -> Level 4 (Rook) • Level 4 - Answer correctly after 1 week -> Level 5 (Queen) • Level 5 - Answer correctly after 3 weeks -> Level 6 (King) • Level 6 - Answer correctly after 9 weeks -> Level 7 (Mastery Achieved) * Remember that if you make a mistake at any point, your level will reset to 0. Each flashcard has the following options: • Learn with shuffled flashcards. • Display the flip side of flashcards first. Night Mode: • Night mode is a switch to a darker theme than usual. • By setting a dark theme, you can use it without straining your eyes even when studying late at night or in bed. • Also, you no longer have to worry about disturbing others with a screen that is too bright.

About

記憶KEEPER

Features
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「いつ復習すればいいか分からない」「問題集を何周もしているのに身につかない」——記憶KEEPERは、忘却曲線にもとづく間隔反復で、資格勉強の“復習タイミング”を自動で管理するアプリです。 【特長】 ・問題番号を登録するだけ。カードを一から作る手間はありません。 ・「今日復習すべき問題」を毎日提示し、勉強の偏りを防ぎます。 ・苦手な問題だけを集中して復習できる「苦手対策」。 ・教材→章→節で整理でき、複数の資格を並行して管理できます。 ・広告なし・余計な通知なし。 【こんな方に】 宅建士・FP・簿記・施工管理技士・行政書士・社労士など、自分の問題集で暗記を進めたい資格受験者の方へ。 今なら無料でご利用いただけます。

Screenshots

THE CURVE4 screens
記憶KEEPER4 screens

Verdict

The call

The clearest difference is ads: 記憶KEEPER at none against THE CURVE's shown. 記憶KEEPER also leads on update cadence (every 3 days vs fortnightly). On price, in-app purchases, device support and iOS requirement 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. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

THE CURVE ships an update fortnightly, 記憶KEEPER every 3 days. The most recent releases landed on November 2, 2026 and October 31, 2026 respectively.

Scorecard2 real differences · 8 level
THE CURVE versus 記憶KEEPER: the parameters behind the verdict, then further details
ParameterTHE CURVE記憶KEEPER
PriceFreeFree
Rating5.0 (2 ratings) — better—
Positive reviews66.7% of reviews—
Number of ratings2 — better—
Update frequencyFortnightlyEvery 3 days — better
AdsYesNo — better
In-app purchasesNoNo
MonetizationAd-supported—
DevicesiPhone, iPodiPhone, iPod
Requires iOS15.015.0
Further details — not scored
Size49 MB4 MB
Age rating4+4+
DeveloperYoshinori Tsuchiyanao watanabe

In-app purchases

None

THE CURVE

No in-app purchases

None

記憶KEEPER

No in-app purchases

Questions

Is THE CURVE free?
THE CURVE is free to download, with no in-app purchases.
Is 記憶KEEPER free?
記憶KEEPER is free to download, with no in-app purchases.
Do THE CURVE or 記憶KEEPER have ads?
THE CURVE shows ads; 記憶KEEPER does not.
Which is updated more often, THE CURVE or 記憶KEEPER?
THE CURVE ships an update fortnightly, and 記憶KEEPER every 3 days. Most recently, THE CURVE was updated on November 2, 2026 and 記憶KEEPER on October 31, 2026.

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