# ThirdCatheter vs 脳観

The clearest difference is price: 脳観 at Free against ThirdCatheter's $1.99. 脳観 also leads on in-app purchases (none vs 3) and iOS requirement (10.0 vs 26.0). ThirdCatheter's advantage is update cadence (every 5 days vs monthly). On review sentiment, ads and device support there is nothing between them.

脳観 is free to download; ThirdCatheter costs $1.99 up front. ThirdCatheter sells 3 in-app purchases, starting at $0.49 per month. 脳観 asks for nothing beyond the download.

ThirdCatheter ships an update every 5 days, 脳観 monthly. The most recent releases landed on November 2, 2026 and October 11, 2026 respectively.

## The numbers

| Metric | ThirdCatheter | 脳観 |
| --- | --- | --- |
| Price | $1.99 | **Free** |
| Rating | — | **[5.0 (1 ratings)](https://appshunter.io/ios/app/id1518722112/reviews)** |
| Number of ratings | — | **1** |
| Positive reviews | 100.0% of reviews | 100.0% of reviews |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Every 5 days** | Monthly |
| Monetization | Free with in-app purchases | — |
| Size | 28 MB | 272 MB |
| Requires iOS | 26.0 | **10.0** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 12+ |
| Developer | [Masaaki Hirata](https://appshunter.io/developer/942972055) | [Satoshi Kiyofuji](https://appshunter.io/developer/1518722111) |

## What reviewers say

### ThirdCatheter

[App page](https://appshunter.io/ios/app/thirdcatheter/id1209823996)

This medical reference tool calculates the theoretical minimum diameter for guiding catheters when using three devices. It offers device data pre-installed in new versions and advanced features like net search and gap imaging evaluation in the paid version. Users are advised to consult device manuals for strategy planning.

**Highlights:** Minimum diameter calculation for guiding catheters, Pre-installed device data, Net search and gap imaging evaluation (paid), Device information sharing via AirDrop, Device data editing with CatheterEditor, Calculates space needed for device function

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| One Month Device Data Use | $0.49 | per month |
| 6 months Device Data Use | $1.99 | per 6 months |
| Fine-tune and save device info. | $1.99 | one-time |


### 脳観

[App page](https://appshunter.io/ios/app/id1518722112)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is ThirdCatheter free?

ThirdCatheter costs $1.99, and also offers in-app purchases.

### Is 脳観 free?

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

### Do ThirdCatheter or 脳観 have ads?

Neither ThirdCatheter nor 脳観 shows ads.

### Which is updated more often, ThirdCatheter or 脳観?

ThirdCatheter ships an update every 5 days, and 脳観 monthly. Most recently, ThirdCatheter was updated on November 2, 2026 and 脳観 on October 11, 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.*