ProbabilityPlayer vs Derivon
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
ProbabilityPlayer
Practice probability problems for the Kyotsu Test, a common Japanese university entrance exam. This app focuses on mathematical probability questions and includes diagrams to aid understanding. It is designed to help students prepare for this specific academic assessment.
- Probability problem practice
- Kyotsu Test focus
- Mathematical probability
- Diagrams included
- University entrance exam prep
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This is an app for Kyotsu Test, the test widely used in Japanese university entrance exams, dealing especially with probability problems in mathematics. I have applied to the rights holder to use the test.
Derivon
Master calculus concepts like derivatives and integrals through daily, intuitive practice. Earn rewards, collect planets, and build streaks as you progress through challenges. Designed for quick, effective learning sessions.
- Daily calculus problem practice
- Earn Star Sand rewards
- Collect planets in Gallery
- Build and maintain daily streaks
- Rank-Up Challenges
- Shooting mode for breaks
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Master calculus through daily practice. Solve derivatives and integrals by intuition — no overthinking, just repetition. • Swipe through problems and build your skills • Earn Star Sand with every correct answer • Spin the Gacha to collect planets in your Gallery • Build a daily streak — never break the chain • Take Rank-Up Challenges as you progress • Play Shooting mode for a quick break • Track your streak, level up, and earn rewards Whether you're preparing for AP Calculus, university exams, or just sharpening your math skills, Derivon makes practice feel like a space adventure. 3 minutes a day. That's all it takes. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/
Screenshots
Verdict
The clearest difference is review sentiment: ProbabilityPlayer at 100% against Derivon's 0%. ProbabilityPlayer also leads on ads (none vs shown) and iOS requirement (18.0 vs 26.0). Derivon's advantage is update cadence (every 2 days vs monthly). On price, in-app purchases, monetization model 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
Both are free to download. ProbabilityPlayer sells 1 one-off in-app purchase and Derivon sells 3 one-off in-app purchases. Whichever you choose, the download price is not the number that matters.
ProbabilityPlayer ships an update monthly, Derivon every 2 days. The most recent releases landed on September 27, 2026 and September 19, 2026 respectively.
| Parameter | ProbabilityPlayer | Derivon |
|---|---|---|
| Price | Free | Free |
| Rating | — | 3.0 (1 ratings) — better |
| Positive reviews | 100.0% of reviews — better | 0.0% of reviews |
| Number of ratings | — | 1 — better |
| Update frequency | Monthly | Every 2 days — better |
| Ads | No — better | Yes |
| In-app purchases | Yes | Yes |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Devices | iPhone, iPad — better | iPhone |
| Requires iOS | 18.0 — better | 26.0 |
| Further details — not scored | ||
| Size | 9 MB | 130 MB |
| Age rating | 4+ | 4+ |
| Developer | Motonari Hibi | RYOMA MIZUTANI |
Customer experience
ProbabilityPlayer
Derivon
In-app purchases
ProbabilityPlayer
- Premium$1.99
Derivon
- 5 Star Fragments$0.99
- 12 Star Fragments$1.99
- 32 Star Fragments$3.99
Questions
Is ProbabilityPlayer free?
Is Derivon free?
Do ProbabilityPlayer or Derivon have ads?
Which is updated more often, ProbabilityPlayer or Derivon?
Other comparisons
