Comparison

Euler’s Number Memory Trainer vs Constant Challenge

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

Head to head
About

Euler’s Number Memory Trainer

Test your memory by memorizing digits of Euler's number. This app provides a simple and helpful interface to challenge your recall of this important mathematical constant.

Highlights
  • Memory skill testing
  • Memorize digits of Euler's number
  • User-friendly interface
  • Simple and helpful design
Features
Read full description

Euler's Number is an app that puts your memory skills to the test and helps you memorize as many digits of Euler’s number as possible. Euler's Number is an irrational mathematical constant, like pi. It was discovered by Leonhard Euler, who was a Swiss mathematician, physicist, astronomer, logician, and engineer of the 18th century. Euler's Number can be derived algebraically and has many useful applications in compound interest, probability theory, derangements, asymptotics, and calculus. Features: • A user-friendly interface. • Astonishingly simple and helpful. • We sincerely consider constructive feedback given in the app reviews.

About

Constant Challenge

Features
Read full description

Constant Challenge is a training app designed to help you memorize mathematical constants like π (pi) and e while testing your skills through various challenge modes. Each constant offers the same set of game modes, allowing you to practice, compete, and improve your memory and speed. Features: - Practice Mode: Learn and memorize digits at your own pace - Time Attack Mode: Enter as many correct digits as possible within a time limit - Stage Mode: Progress through structured levels of increasing difficulty - Local Battle Mode: Competitive play possible Track your performance, challenge yourself, and aim for high scores. Perfect for students, math enthusiasts, and anyone who enjoys memory challenges. Note: This app focuses on memorization and training of mathematical constants.

Screenshots

Euler’s Number Memory Trainer2 screens
Constant Challenge4 screens

Verdict

The call

The clearest difference is in-app purchases: Euler’s Number Memory Trainer at none against Constant Challenge's 3. Euler’s Number Memory Trainer also leads on iOS requirement (11.2 vs 26.0). Constant Challenge's advantage is update cadence (every 2 days vs monthly). On price, ads 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. Constant Challenge sells 3 one-off in-app purchases. Euler’s Number Memory Trainer asks for nothing beyond the download.

UpkeepUpdate frequency

Euler’s Number Memory Trainer ships an update monthly, Constant Challenge every 2 days. The most recent releases landed on October 24, 2026 and September 28, 2026 respectively.

Scorecard3 real differences · 6 level
Euler’s Number Memory Trainer versus Constant Challenge: the parameters behind the verdict, then further details
ParameterEuler’s Number Memory TrainerConstant Challenge
PriceFreeFree
Rating2.3 (3 ratings) — better—
Number of ratings3 — better—
Update frequencyMonthlyEvery 2 days — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree—
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS11.2 — better26.0
Further details — not scored
Size12 MB16 MB
Age rating4+4+
DeveloperMatthew TurkKaname Inoue

In-app purchases

None

Euler’s Number Memory Trainer

No in-app purchases

3 purchases

Constant Challenge

One-time3
  • Unlock the Square Root of 2 (√2)$0.99
  • Unlock the Golden Ratio (φ)$0.99
  • Unlock the Euler–Mascheroni (γ)$0.99

Questions

Is Euler’s Number Memory Trainer free?
Euler’s Number Memory Trainer is free to download, with no in-app purchases.
Is Constant Challenge free?
Constant Challenge is free to download, with in-app purchases available.
Do Euler’s Number Memory Trainer or Constant Challenge have ads?
Neither Euler’s Number Memory Trainer nor Constant Challenge shows ads.
Which is updated more often, Euler’s Number Memory Trainer or Constant Challenge?
Euler’s Number Memory Trainer ships an update monthly, and Constant Challenge every 2 days. Most recently, Euler’s Number Memory Trainer was updated on October 24, 2026 and Constant Challenge on September 28, 2026.

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