# iDeco Pro vs The O2ptimaCM Checklist

The clearest difference is rating: The O2ptimaCM Checklist at 5.0 against iDeco Pro's 3.9. The O2ptimaCM Checklist also leads on update cadence (every 4 months vs every 18 months). iDeco Pro's advantage is in-app purchases (none vs 4) and ratings volume (10 vs 1). On ads, monetization model and device support there is nothing between them.

iDeco Pro costs $8.99 and The O2ptimaCM Checklist $9.99 up front. The O2ptimaCM Checklist sells 4 one-off in-app purchases. iDeco Pro asks for nothing beyond the download.

The O2ptimaCM Checklist holds the better App Store score, 5.0 against 3.9. That said, the two scores are not equally well evidenced: iDeco Pro has 10 ratings behind it against 1, so its average is the more settled of the two.

iDeco Pro ships an update every 18 months, The O2ptimaCM Checklist every 4 months. The most recent releases landed on November 10, 2026 and November 7, 2026 respectively.

## The numbers

| Metric | iDeco Pro | The O2ptimaCM Checklist |
| --- | --- | --- |
| Price | **$8.99** | $9.99 |
| Rating | [3.9 (10 ratings)](https://appshunter.io/ios/app/ideco-pro/id329772936/reviews) | **[5.0 (1 ratings)](https://appshunter.io/ios/app/the-o2ptimacm-checklist/id6469104578/reviews)** |
| Number of ratings | **10** | 1 |
| Positive reviews | 52.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 18 months | **Every 4 months** |
| Monetization | Paid | Paid |
| Size | 3 MB | 2 MB |
| Requires iOS | **7.0** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [B2 Prototech LLC](https://appshunter.io/developer/1575972363) | [Andrew Austin](https://appshunter.io/developer/1708589155) |

## What reviewers say

### iDeco Pro

[App page](https://appshunter.io/ios/app/ideco-pro/id329772936)

This app is a comprehensive dive planner for technical divers, supporting both open circuit and closed-circuit rebreather (CCR) diving. It calculates decompression stops, gas usage, CNS and OTU exposure, and surface intervals. The app also includes a gas mixer for planning custom gas blends.

**Highlights:** Open Circuit and CCR dive planning, Decompression stop calculation, Gas usage and CNS/OTU tracking, Surface interval tracking, Gas fill/mixer functionality, Bailout planning for overhead environments, Configurable settings within the app

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

**In-app purchases:** none


### The O2ptimaCM Checklist

[App page](https://appshunter.io/ios/app/the-o2ptimacm-checklist/id6469104578)

This app provides digital checklists for rebreather assembly, helping divers manage their build process. It includes countdown timers for critical breathing stages and a summary view with caution alerts for missed steps. Transition from paper to a digital format for efficient and environmentally friendly diving preparation.

**Highlights:** Digital rebreather assembly checklists, Countdown timers for breathing stages, Summary view of build progress, Caution blocks for missed steps, Paperless dive preparation

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

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Tiny Tip | $0.99 | one-time |
| Small Tip | $1.99 | one-time |
| Medium Tip | $4.99 | one-time |
| Large Tip | $9.99 | one-time |


## Frequently asked questions

### Is iDeco Pro free?

iDeco Pro costs $8.99, with no in-app purchases.

### Is The O2ptimaCM Checklist free?

The O2ptimaCM Checklist costs $9.99, and also offers in-app purchases.

### Which has better reviews, iDeco Pro or The O2ptimaCM Checklist?

The O2ptimaCM Checklist is rated higher. iDeco Pro averages 3.9 out of 5 from 10 ratings, while The O2ptimaCM Checklist averages 5.0 from 1 ratings.

### Do iDeco Pro or The O2ptimaCM Checklist have ads?

Neither iDeco Pro nor The O2ptimaCM Checklist shows ads.

### Which is updated more often, iDeco Pro or The O2ptimaCM Checklist?

iDeco Pro ships an update every 18 months, and The O2ptimaCM Checklist every 4 months. Most recently, iDeco Pro was updated on November 10, 2026 and The O2ptimaCM Checklist on November 7, 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.*