# Uncertainty Calculator vs Study Timer & Time Tracker

The clearest difference is price: Study Timer & Time Tracker at Free against Uncertainty Calculator's $3.99. Study Timer & Time Tracker also leads on update cadence (every 4 days vs every 3 months) and ratings volume (25 vs 1). Uncertainty Calculator's advantage is rating (5.0 vs 4.3) and in-app purchases (none vs 1). On device support and iOS requirement there is nothing between them.

Study Timer & Time Tracker is free to download; Uncertainty Calculator costs $3.99 up front. Study Timer & Time Tracker sells 1 one-off in-app purchase. Uncertainty Calculator asks for nothing beyond the download.

Uncertainty Calculator holds the better App Store score, 5.0 against 4.3. That said, the two scores are not equally well evidenced: Study Timer & Time Tracker has 25 ratings behind it against 1, so its average is the more settled of the two.

Uncertainty Calculator ships an update every 3 months, Study Timer & Time Tracker every 4 days. The most recent releases landed on September 14, 2026 and September 24, 2026 respectively.

## The numbers

| Metric | Uncertainty Calculator | Study Timer & Time Tracker |
| --- | --- | --- |
| Price | $3.99 | **Free** |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/uncertainty-calculator/id1170905440/reviews)** | [4.3 (25 ratings)](https://appshunter.io/ios/app/study-timer-and-time-tracker/id1644638467/reviews) |
| Number of ratings | 1 | **25** |
| Positive reviews | — | 80.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 3 months | **Every 4 days** |
| Monetization | Paid | **Ad-supported** |
| Size | 1 MB | 35 MB |
| Requires iOS | 17.0 | **16.6** |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Roman Volinsky](https://appshunter.io/developer/977951850) | [WEBDIA INC.](https://appshunter.io/developer/1271616115) |

## What reviewers say

### Uncertainty Calculator

[App page](https://appshunter.io/ios/app/uncertainty-calculator/id1170905440)

This app allows users to perform error propagation calculations for mathematical expressions involving uncertain variables. It supports absolute and relative error inputs, various functions, and trigonometric calculations in degrees or radians. The tool helps ensure accurate reporting of results based on estimated errors.

**Highlights:** Error propagation calculations, Absolute and relative error input, Support for mathematical functions, Trigonometric calculations (degrees/radians), Variable combination in expressions, Significant figure guidance

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


### Study Timer & Time Tracker

[App page](https://appshunter.io/ios/app/study-timer-and-time-tracker/id1644638467)

Easily track your daily study sessions and visualize your progress with detailed history charts. This app helps you identify subjects needing more attention, encouraging balanced learning for improved academic performance.

**Highlights:** Record study time by subject, Register and manage subjects, View study history with graphs, Visualize time spent on weak subjects, Ad-supported free usage

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Remove Ads | $2.99 | one-time |


## Frequently asked questions

### Is Uncertainty Calculator free?

Uncertainty Calculator costs $3.99, with no in-app purchases.

### Is Study Timer & Time Tracker free?

Study Timer & Time Tracker is free to download, with in-app purchases available.

### Which has better reviews, Uncertainty Calculator or Study Timer & Time Tracker?

Uncertainty Calculator is rated higher. Uncertainty Calculator averages 5.0 out of 5 from 1 ratings, while Study Timer & Time Tracker averages 4.3 from 25 ratings.

### Do Uncertainty Calculator or Study Timer & Time Tracker have ads?

Study Timer & Time Tracker shows ads; Uncertainty Calculator does not.

### Which is updated more often, Uncertainty Calculator or Study Timer & Time Tracker?

Uncertainty Calculator ships an update every 3 months, and Study Timer & Time Tracker every 4 days. Most recently, Uncertainty Calculator was updated on September 14, 2026 and Study Timer & Time Tracker on September 24, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*