# σT — Code-Free Error Propagation

> Code-Free Error Propagation (iPhone/iPad app by YARON AMIR BENJAMIN DR. GOLDSTEIN.)

- Source: https://appshunter.io/ios/app/t/id6756549182 (this page in markdown: same URL + `.md`)
- Developer: [YARON AMIR BENJAMIN DR. GOLDSTEIN](https://appshunter.io/developer/1850455880)
- Category: Education, Utilities
- Price: Free
- Age rating: 4+
- Requires: iOS 26.2 · 6 MB
- Languages: English
- Released: 2025-12-23
- Data updated: 2026-06-30
- User reviews in markdown: https://appshunter.io/ios/app/t/id6756549182/reviews.md

## What is σT?

σT is a precision tool for physics students and researchers who need to propagate measurement uncertainties through calculations. Enter your experimental data, and σT handles the error math automatically.


**FIVE ERROR MODES**

Configure uncertainties in your data to match your orignal measurement method:
• Constant — for physical constants and exact values
• Absolute — fixed ±error (ruler measurements, digital readouts)
• Relative — percentage-based uncertainty
• Combined — both absolute and relative components (many typical multimeters)
• Per-Value — individual error for each measurement


**AUTOMATIC PROPAGATION**

Create derived values and watch uncertainties flow through the calculation chain. σT uses Gaussian error-propagation and pre-calculated derivative-based methods to compute propagated errors correctly when combining independently measured variables.

Available operations:
• Basic: add, subtract, multiply, divide, reciprocal
• Functions: exp, ln, sin, cos, normalize
• Statistical & Sample Statistics: mean with standard error, average step width
• Advanced: weighted sums, weighted products, polynomials
• Physics: Lorentz factor (relativistic gamma), Logit sigmoid (Fermi-Dirac statistics)


**INTERACTIVE CHARTS**

Visualize your data with proper error bars. Pinch to zoom, drag to pan, double-tap to auto-fit. Add mathematical function overlays to compare your measurements against theoretical predictions, identify eligible parameter ranges matching your measurements.


**EXPORT YOUR WORK**

• CSV and TSV export for spreadsheets and analysis tools
• High-resolution PNG charts for lab reports
• Complete project files for sharing with classmates or colleagues
• Copy data to clipboard with a swipe and continue in Sheets or Excel with errors in place


**DESIGNED FOR LAB WORK**

σT adapts to your device:
• iPhone: Full-featured portable lab companion
• iPad: Side-by-side layout for efficient data entry
• Mac: Native desktop experience via Catalyst


**YOUR DATA, YOUR DEVICE**

All measurements are stored locally. No account required, no cloud sync, no tracking. σT works completely offline.


## Version history (last 5 releases)

### 1.5 — 2026-06-12

Evaluate data more easily with optional log-scaled axes in your charts.
When you add lines into charts, extract parameters automatically based on the corresponding axis transformation. log-y and regular x? Extract the parameters that model y ~ A * exp(lambda x)!

### 1.4 — 2026-05-28

What’s New in Version 1.4

This update focuses on faster physics workflows, stronger data analysis, and better chart tooling.

## Distribution Analysis & Normal Testing
Added a dedicated Distribution Analysis workspace to evaluate how measured or derived series compare to normal-distribution behavior.

## Redesigned, movable Charts
- manually place and move reference/fit lines
- fit normal distributions over peaks
- export fitted function parameters back into the worksheet

## Quality of life updates:
- Added a new Const library of known derived formula templates you can insert into a worksheet in one tap (as editable, formula-linked derived values).
- Added a Migration Assistant to help update multiple co-dependent worksheet fields together for easier worksheet reuse.
- More flexible import: Import measurement series not only as column vectors, but also as comma separated list

### 1.3.2 — 2026-05-01

/ Built in support for the most common constants
/ Visual overhaul for creating derived values, so you need to click less

### 1.2 — 2026-01-08

Version 1.2

Sample Statistics from Raw Data:
Turn a list of constant values directly into a sample mean with its standard deviation as the uncertainty estimate. Perfect for repeated measurements where you want σT to compute the statistics for you.

Pivot Tables:
Reshape long-format data into cross-tabulated views. Select columns for row labels, column headers, and values—then aggregate by mean, sum, or product. Further process the results, e.g., take the log of the results. Ideal for comparing conditions across experimental runs or simple A/B analyses. Includes built-in visualization of the resulting table.

### 1.0 — 2025-12-23

No release notes.

## More apps by YARON AMIR BENJAMIN DR. GOLDSTEIN

- [TeaLoveLog](https://appshunter.io/ios/app/tealovelog/id6754843586)
- [YARON FA](https://appshunter.io/ios/app/yaron-fa/id6757681266)
- [David's Dual Time Keeper](https://appshunter.io/ios/app/davids-dual-time-keeper/id6757792838)
- [Ket Steps](https://appshunter.io/ios/app/ket-steps/id6762529698)
- [Markdown My Words](https://appshunter.io/ios/app/markdown-my-words/id6764109236)

All apps by YARON AMIR BENJAMIN DR. GOLDSTEIN: https://appshunter.io/developer/1850455880

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-06-30.*