# Volumetric Method Simulator vs Colnn

The clearest difference is price: Colnn at Free against Volumetric Method Simulator's $19.99. Colnn also leads on update cadence (every 4 weeks vs every 26 months). On ads, in-app purchases, device support and iOS requirement there is nothing between them.

Colnn is free to download; Volumetric Method Simulator costs $19.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Volumetric Method Simulator ships an update every 26 months, Colnn every 4 weeks. The most recent releases landed on October 5, 2026 and October 3, 2026 respectively.

## The numbers

| Metric | Volumetric Method Simulator | Colnn |
| --- | --- | --- |
| Price | $19.99 | **Free** |
| Rating | — | **[1.9 (20 ratings)](https://appshunter.io/ios/app/colnn/id1533972641/reviews)** |
| Number of ratings | — | **20** |
| Positive reviews | — | 0.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 26 months | **Every 4 weeks** |
| Monetization | — | Free |
| Size | 20 MB | 80 MB |
| Requires iOS | **12.0** | 12.4 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Carlos Moura](https://appshunter.io/developer/407501202) | [Tamer Badawy](https://appshunter.io/developer/1771877290) |

## What reviewers say

### Volumetric Method Simulator

[App page](https://appshunter.io/ios/app/volumetric-method-simulator/id1475024726)

**Features:** Vision Pro support

**In-app purchases:** none


### Colnn

[App page](https://appshunter.io/ios/app/colnn/id1533972641)

Stay connected with your school, track academic progress, and manage school-related information. Students can view timetables, homework, and grades, while parents can monitor financial data and communicate with the administration.

**Highlights:** Classroom timetable viewing, Homework and assignment tracking, Digital library access, School news updates, Attendance monitoring, Exam details and results, Financial data for parents, Direct communication with school administration

**In-app purchases:** none


## Frequently asked questions

### Is Volumetric Method Simulator free?

Volumetric Method Simulator costs $19.99, with no in-app purchases.

### Is Colnn free?

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

### Do Volumetric Method Simulator or Colnn have ads?

Neither Volumetric Method Simulator nor Colnn shows ads.

### Which is updated more often, Volumetric Method Simulator or Colnn?

Volumetric Method Simulator ships an update every 26 months, and Colnn every 4 weeks. Most recently, Volumetric Method Simulator was updated on October 5, 2026 and Colnn on October 3, 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.*