Goldbach's Conjecture vs Cabri Express Primary
Price, ratings, monetisation and update history for both apps, side by side โ with what reviewers say about each.
Goldbach's Conjecture
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Fun and Challenging! Goldbach's Conjecture introduces students to an idea that has baffled mathematicians for centuries. In 1742, a Russian mathematician named Christian Goldbach wrote a letter to Leonhard Euler in which he proposed a conjecture. The conjecture stated that all even numbers greater than two can be expressed as the sum of two primes. This app challenges the player to find two prime numbers to make a target even number. Completing the activity involves using mental math skills. Goldbach Conjecture is designed to be a quick math exercise that teachers can use to provide extra practice in problem solving and an enriching experience for their students. Special sound effects make the game fun to use and the interactive design facilitate problem solving strategies.
Cabri Express Primary
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Features of Cabri Express Primary include a super easy primary calculator, geometry instruments, 2D & 3D shapes plus a dynamic geometry environment. App wrapped in an intuitive app that kids love to use. The primary version distinguishes itself from the secondary version in the look and in the calculator: the division is arithmetic (per default) and decimal numbers, fractions, roots and trigonometric functions are not made extra visible. These adjustments are the results of reviews with math education experts and with ministries of education. With its friendly interface, Cabri Express allows students to visualize and manipulate abstract mathematical concepts. The app is a laboratory in which they explore, model, and investigate without any limits. Cabri is free, it is the reference software for dynamic mathematics. It has been used for more than 25 years by millions of teachers and students around the world. Good maths for students and power & ease for teachers, to teach math not the software.
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Verdict
The clearest difference is price: Cabri Express Primary at Free against Goldbach's Conjecture's $0.99. Cabri Express Primary also leads on update cadence (every 2 months vs every 8 months) and device support (4 vs 2). Goldbach's Conjecture's advantage is iOS requirement (12.0 vs 14.0). On ads and in-app purchases there is nothing between them.
Scored on Price ยท Rating ยท Positive reviews ยท Number of ratings ยท Update frequency ยท Ads ยท In-app purchases ยท Monetization ยท Best chart rank ยท Devices ยท Requires iOS
Cabri Express Primary is free to download; Goldbach's Conjecture costs $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.
Goldbach's Conjecture ships an update every 8 months, Cabri Express Primary every 2 months. Both last shipped on October 3, 2026.
| Parameter | Goldbach's Conjecture | Cabri Express Primary |
|---|---|---|
| Price | $0.99 | Free โ better |
| Update frequency | Every 8 months | Every 2 months โ better |
| Ads | No | No |
| In-app purchases | No | No |
| Devices | iPad, Mac | iPhone, iPad, iPod, Mac โ better |
| Requires iOS | 12.0 โ better | 14.0 |
| Further details โ not scored | ||
| Size | 34 MB | 101 MB |
| Age rating | 4+ | 12+ |
| Developer | Ventura Educational Systems | Cabrilog SAS |
In-app purchases
Goldbach's Conjecture
No in-app purchases
Cabri Express Primary
No in-app purchases
Questions
Is Goldbach's Conjecture free?
Is Cabri Express Primary free?
Do Goldbach's Conjecture or Cabri Express Primary have ads?
Which is updated more often, Goldbach's Conjecture or Cabri Express Primary?
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