# SISO Calculator vs Control Systems Engineering

The clearest difference is in-app purchases: SISO Calculator at none against Control Systems Engineering's 6. SISO Calculator also leads on update cadence (every 5 weeks vs every 3 months) and device support (3 vs 1). On price and ads there is nothing between them.

Both are free to download. Control Systems Engineering sells 6 in-app purchases, starting at $9.99 per month. SISO Calculator asks for nothing beyond the download.

SISO Calculator ships an update every 5 weeks, Control Systems Engineering every 3 months. The most recent releases landed on June 3, 2026 and September 14, 2026 respectively.

## The numbers

| Metric | SISO Calculator | Control Systems Engineering |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (3 ratings)](https://appshunter.io/ios/app/siso-calculator/id1548141101/reviews)** | — |
| Number of ratings | **3** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Every 5 weeks** | Every 3 months |
| Monetization | Free | — |
| Size | 4 MB | 18 MB |
| Requires iOS | **14.0** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Deft Dynamics LLC](https://appshunter.io/developer/1288783778) | [Forwa Elade Wunde](https://appshunter.io/developer/1685241344) |

## What reviewers say

### SISO Calculator

[App page](https://appshunter.io/ios/app/siso-calculator/id1548141101)

This app helps engineers and students understand System Dynamics and Controls. It offers an intuitive interface to quickly analyze controller and plant interactions in both time and frequency domains.

**Highlights:** System Dynamics analysis, Controls engineering, Intuitive interface, Time domain analysis, Frequency domain analysis, Controller interaction visualization

**Features:** macOS Compatibility

**In-app purchases:** none


### Control Systems Engineering

[App page](https://appshunter.io/ios/app/control-systems-engineering/id6739731886)

**Features:** macOS Compatibility

**In-app purchases (6)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 1 Month | $9.99 | per month |
| 6 Months | $19.99 | per 6 months |
| 1 Year | $29.99 | per year |
| 1500 | $0.99 | one-time |
| 3500 | $1.99 | one-time |
| 9000 | $3.99 | one-time |


## Frequently asked questions

### Is SISO Calculator free?

SISO Calculator is free to download, with no in-app purchases.

### Is Control Systems Engineering free?

Control Systems Engineering is free to download, with in-app purchases available.

### Do SISO Calculator or Control Systems Engineering have ads?

Neither SISO Calculator nor Control Systems Engineering shows ads.

### Which is updated more often, SISO Calculator or Control Systems Engineering?

SISO Calculator ships an update every 5 weeks, and Control Systems Engineering every 3 months. Most recently, SISO Calculator was updated on June 3, 2026 and Control Systems Engineering on September 14, 2026.

---

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