# DWSIM Simulator vs Severe Service

The clearest difference is in-app purchases: Severe Service at none against DWSIM Simulator's 10. DWSIM Simulator's advantage is ratings volume (105 vs 7). On price, rating, update cadence and ads there is nothing between them.

Both are free to download. DWSIM Simulator sells 10 one-off in-app purchases. Severe Service asks for nothing beyond the download.

On the App Store both sit at effectively the same score — 4.6 for DWSIM Simulator against 4.7 for Severe Service. That said, the two scores are not equally well evidenced: DWSIM Simulator has 105 ratings behind it against 7, so its average is the more settled of the two.

DWSIM Simulator ships an update every 6 weeks, Severe Service monthly. The most recent releases landed on September 13, 2026 and September 16, 2026 respectively.

## The numbers

| Metric | DWSIM Simulator | Severe Service |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.6 (105 ratings)](https://appshunter.io/ios/app/dwsim-simulator/id1162110266/reviews) | **[4.7 (7 ratings)](https://appshunter.io/ios/app/severe-service/id1436753584/reviews)** |
| Number of ratings | **105** | 7 |
| Positive reviews | 57.1% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 6 weeks | **Monthly** |
| Monetization | Free | Free |
| Size | 106 MB | 26 MB |
| Requires iOS | **12.0** | 13.2 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Daniel Medeiros](https://appshunter.io/developer/1091004600) | [Emerson Process Management](https://appshunter.io/developer/561985742) |

## What reviewers say

### DWSIM Simulator

[App page](https://appshunter.io/ios/app/dwsim-simulator/id1162110266)

This app provides a powerful offline chemical process simulation tool. It allows engineers to build complex process models, perform thermodynamic calculations, and analyze various unit operations. Features include a touch-enabled PFD interface, extensive compound databases, and advanced calculation engines.

**Highlights:** Offline chemical process simulation, Touch-enabled PFD drawing interface, Extensive thermodynamic models, Compound database for 1500+ compounds, Unit operation models, Chemical reaction and reactor support, Flowsheet parametric studies

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

**In-app purchases (10)**

| Purchase | Price | Billing |
| --- | --- | --- |
| User-Defined Unit Set | $1.99 | one-time |
| Flowsheet Utilities Pack | $2.99 | one-time |
| Unit Operations Pack 1 | $2.99 | one-time |
| Unit Operations Pack 2 | $2.99 | one-time |
| Unit Operations Pack 3 | $2.99 | one-time |
| Activity Coeff. Model Pack | $3.99 | one-time |
| Equation of State Model Pack | $3.99 | one-time |
| Reactor Models Pack | $4.99 | one-time |
| Unlock All Features | $9.99 | one-time |
| Unlock All Features | $39.99 | one-time |


### Severe Service

[App page](https://appshunter.io/ios/app/severe-service/id1436753584)

This app helps users perform initial sizing for control valves, diagnose issues by selecting symptoms, and explore severe service applications across various industries. It also provides access to a technical library with videos and PDFs, a product catalog, and a contact feature for expert assistance.

**Highlights:** Control valve sizing tool, Issue diagnosis by symptom, Industry application explorer, Technical library with videos and PDFs, Fisher product catalog, Keyword search functionality, Direct contact with experts

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is DWSIM Simulator free?

DWSIM Simulator is free to download, with in-app purchases available.

### Is Severe Service free?

Severe Service is free to download, with no in-app purchases.

### Which has better reviews, DWSIM Simulator or Severe Service?

Severe Service is rated higher. DWSIM Simulator averages 4.6 out of 5 from 105 ratings, while Severe Service averages 4.7 from 7 ratings.

### Do DWSIM Simulator or Severe Service have ads?

Neither DWSIM Simulator nor Severe Service shows ads.

### Which is updated more often, DWSIM Simulator or Severe Service?

DWSIM Simulator ships an update every 6 weeks, and Severe Service monthly. Most recently, DWSIM Simulator was updated on September 13, 2026 and Severe Service on September 16, 2026.

---

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