Probability Distribution vs Caliper
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Probability Distribution
This app allows users to calculate probabilities and visualize various continuous and discrete probability distributions. It supports a wide range of common distributions and plans to add more in the future.
- Calculate probabilities
- Visualize distributions
- Normal (Gaussian) distribution
- Binomial distribution
- Poisson distribution
- Exponential distribution
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Calculate probabilities and visualize probability distributions. Supported continuous probability distributions: - Normal (Gaussian) - t (Student's t) - Chi-Squared - F - Exponential - Gamma - Beta - Log-normal Supported discrete probability distributions: - Binomial - Poisson - Pascal - Geometric - Hypergeometric and more are coming.
Caliper
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Learn how to read a metric 0.02 mm vernier caliper, one step at a time. Practice on an interactive instrument, understand how the scales line up, and build confidence before using a real caliper. UNDERSTAND THE READING Find the vernier zero, read the whole millimetres, identify the matching line and calculate the final measurement. Follow the guided introduction, then apply the method yourself. BUILD YOUR SKILLS Progress through 30 short levels covering reading, precision, setting measurements and timed challenges. PRACTICE THREE WAYS • Read: identify the measurement shown on the scale. • Set: move the jaw to a target measurement, with fine adjustments in 0.02 mm steps. • Speed: work through 10 timed challenges and review your accuracy, response time and best streak. SEE THE DETAILS Zoom in and move around the scale to inspect its markings. Use Fit Whole Scale to return to the complete view. START FREE The guided introduction and first five levels are free. A single in-app purchase unlocks levels 6–30 and unlimited Read, Set and Speed practice. No subscription or account required. Designed for students, apprentices and anyone learning to use a metric vernier caliper. This is a training simulator; it does not measure physical objects with your phone.
Screenshots
Verdict
The clearest difference is update cadence: Caliper at every 2 days against Probability Distribution's every 2 weeks. 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
Both are free to download. Probability Distribution sells 1 one-off in-app purchase and Caliper sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.
Probability Distribution ships an update every 2 weeks, Caliper every 2 days. The most recent releases landed on October 12, 2026 and October 9, 2026 respectively.
| Parameter | Probability Distribution | Caliper |
|---|---|---|
| Price | Free | Free |
| Rating | 4.5 (15 ratings) — better | — |
| Positive reviews | 33.3% of reviews | — |
| Number of ratings | 15 — better | — |
| Update frequency | Every 2 weeks | Every 2 days — better |
| Ads | No | No |
| In-app purchases | Yes | Yes |
| Monetization | Paid | — |
| Devices | iPhone, iPad — better | iPhone |
| Requires iOS | 16.0 — better | 16.4 |
| Further details — not scored | ||
| Size | 7 MB | 36 MB |
| Age rating | 4+ | 4+ |
| Developer | Madiyar Aitbayev | Concept of Proof B.V. |
In-app purchases
Probability Distribution
- Unlock All Distributions$2.99
Caliper
- Caliper Full Access$2.99
Questions
Is Probability Distribution free?
Is Caliper free?
Do Probability Distribution or Caliper have ads?
Which is updated more often, Probability Distribution or Caliper?
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