# IDDA vs Decosoft

The clearest difference is review sentiment: Decosoft at 100% against IDDA's 0%. IDDA's advantage is in-app purchases (none vs 8). On price, update cadence, ads and device support there is nothing between them.

Both are free to download. Decosoft sells 8 in-app purchases, starting at $3.99 per month. IDDA asks for nothing beyond the download.

Both ship on a similar rhythm, roughly every 2 weeks. The most recent releases landed on October 5, 2026 and October 8, 2026 respectively.

## The numbers

| Metric | IDDA | Decosoft |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | 0.0% of reviews | **100.0% of reviews** |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 2 weeks | Every 2 weeks |
| Monetization | **Free** | Free with in-app purchases |
| Size | 37 MB | 47 MB |
| Requires iOS | **15.6** | 16.4 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 12+ | 4+ |
| Developer | [IDDA GmbH](https://appshunter.io/developer/1663006167) | [Michael Czolko](https://appshunter.io/developer/674555865) |

## What reviewers say

### IDDA

[App page](https://appshunter.io/ios/app/idda/id1663006165)

This platform offers e-learning content and certifications to enhance diving knowledge and prepare for exams. It's designed to make learning and exam preparation more accessible for divers. Future updates promise even more features to support your diving journey.

**Highlights:** E-learning content, Brevet platform, Diving knowledge enhancement, Exam preparation, Accessible learning

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

**In-app purchases:** none


### Decosoft

[App page](https://appshunter.io/ios/app/decosoft/id6453846218)

Plan your dives with this comprehensive tech diving tool. It offers a user-friendly interface, advanced decompression models, and various dive calculators to ensure safe and enjoyable underwater adventures. Save, share, and prepare for every dive with detailed insights.

**Highlights:** User-friendly dive planning interface, Bühlmann decompression model, Detailed runtime table with graphs, Support for OC and CCR, Multiple dive calculators, Save and share dive plans

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

**In-app purchases (8)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Monthly Partner | $3.99 | per month |
| Monthly | $3.99 | per month |
| Annual Partners | $39.99 | per year |
| Ultimate | $39.99 | per year |
| Ultimate Offer | $39.99 | per year |
| Ultimate | $20.99 | one-time |
| Ultimate | $23.99 | one-time |
| Ultimate | $29.99 | one-time |


## Frequently asked questions

### Is IDDA free?

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

### Is Decosoft free?

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

### Do IDDA or Decosoft have ads?

Neither IDDA nor Decosoft shows ads.

### Which is updated more often, IDDA or Decosoft?

IDDA ships an update every 2 weeks, and Decosoft every 2 weeks. Most recently, IDDA was updated on October 5, 2026 and Decosoft on October 8, 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.*