# HyTools vs testo 330i App

The clearest difference is rating: HyTools at 4.0 against testo 330i App's 3.0. HyTools also leads on update cadence (every 6 weeks vs every 4 months) and review sentiment (50% vs 38%). testo 330i App's advantage is iOS requirement (12 vs 15.0). On price, ratings volume, ads and in-app purchases there is nothing between them.

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

HyTools holds the better App Store score, 4.0 against 3.0. Both are backed by a comparable volume of ratings — 5 and 2 respectively. Written reviews point the same way: 50% of HyTools's written reviews are positive against 38% of testo 330i App's.

HyTools ships an update every 6 weeks, testo 330i App every 4 months. The most recent releases landed on September 28, 2026 and October 12, 2026 respectively.

## The numbers

| Metric | HyTools | testo 330i App |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.0 (5 ratings)](https://appshunter.io/ios/app/hytools/id537674477/reviews)** | [3.0 (2 ratings)](https://appshunter.io/ios/app/testo-330i-app/id1007290554/reviews) |
| Number of ratings | **5** | 2 |
| Positive reviews | **50.0% of reviews** | 37.5% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 6 weeks** | Every 4 months |
| Monetization | Free | Free |
| Size | 114 MB | 52 MB |
| Requires iOS | 15.0 | **12** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [IMI Hydronic Engineering International SA](https://appshunter.io/developer/508015425) | [Testo SE & Co. KGaA](https://appshunter.io/developer/966489178) |

## What reviewers say

### HyTools

[App page](https://appshunter.io/ios/app/hytools/id537674477)

This app provides HVAC professionals with a comprehensive suite of hydronic calculation tools. It assists with tasks like valve sizing, pressure drop calculations, and radiator power estimation. The tool offers unit conversion and language selection for user convenience.

**Highlights:** Hydronic calculator, Valve sizing and presetting, Radiator power estimation, Pipe sizing, Unit conversion, Pressure maintenance calculation

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

**In-app purchases:** none


### testo 330i App

[App page](https://appshunter.io/ios/app/testo-330i-app/id1007290554)

Control your testo 330i flue gas analyzer remotely from your smartphone or tablet. View live measurement values, create detailed PDF reports with photos and your logo, and send them directly from the field. Offers a graphical trend view and data export options.

**Highlights:** Complete analyzer control via smartphone/tablet, Intuitive touchscreen handling, Graphical trend view, PDF report creation, Export measurement values (CSV, ZIV), Insert photos and comments into reports, Bluetooth connectivity (20m range)

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

**In-app purchases:** none


## Frequently asked questions

### Is HyTools free?

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

### Is testo 330i App free?

testo 330i App is free to download, with no in-app purchases.

### Which has better reviews, HyTools or testo 330i App?

HyTools is rated higher. HyTools averages 4.0 out of 5 from 5 ratings, while testo 330i App averages 3.0 from 2 ratings.

### Do HyTools or testo 330i App have ads?

Neither HyTools nor testo 330i App shows ads.

### Which is updated more often, HyTools or testo 330i App?

HyTools ships an update every 6 weeks, and testo 330i App every 4 months. Most recently, HyTools was updated on September 28, 2026 and testo 330i App on October 12, 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.*