# Nyquist App vs And Theory

The clearest difference is update cadence: And Theory at weekly against Nyquist App's every 10 months. On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Nyquist App ships an update every 10 months, And Theory weekly. The most recent releases landed on October 18, 2026 and October 4, 2026 respectively.

## The numbers

| Metric | Nyquist App | And Theory |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/nyquist-app/id1444291209/reviews)** | — |
| Number of ratings | **1** | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 10 months | **Weekly** |
| Monetization | Free | — |
| Size | 22 MB | 62 MB |
| Requires iOS | 13.0 | 13.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 17+ |
| Developer | [Patricia Pauli](https://appshunter.io/developer/1587769862) | [and Theory LTD](https://appshunter.io/developer/1714944253) |

## What reviewers say

### Nyquist App

[App page](https://appshunter.io/ios/app/nyquist-app/id1444291209)

Practice the Nyquist stability criterion to determine closed-loop stability from open-loop frequency response. Developed for an introductory control engineering course, this app offers self-contained content for anyone interested in the topic.

**Highlights:** Nyquist stability criterion practice, Determine closed-loop stability, Frequency response analysis, Self-contained educational content, Developed for control engineering course

**Features:** macOS Compatibility

**In-app purchases:** none


### And Theory

[App page](https://appshunter.io/ios/app/and-theory/id6471235374)

**Features:** macOS Compatibility, Apple Wallet

**In-app purchases:** none


## Frequently asked questions

### Is Nyquist App free?

Nyquist App is free to download, with no in-app purchases.

### Is And Theory free?

And Theory is free to download, with no in-app purchases.

### Do Nyquist App or And Theory have ads?

Neither Nyquist App nor And Theory shows ads.

### Which is updated more often, Nyquist App or And Theory?

Nyquist App ships an update every 10 months, and And Theory weekly. Most recently, Nyquist App was updated on October 18, 2026 and And Theory on October 4, 2026.

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