# i vs 脊椎セラピーV3（マスターV3)

The clearest difference is update cadence: i at every 2 months against 脊椎セラピーV3（マスターV3)'s every 38 months. 脊椎セラピーV3（マスターV3)'s advantage is iOS requirement (12.0 vs 15.0). On price, ads, in-app purchases and device support there is nothing between them.

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

i ships an update every 2 months, 脊椎セラピーV3（マスターV3) every 38 months. The most recent releases landed on October 10, 2026 and October 26, 2026 respectively.

## The numbers

| Metric | i | 脊椎セラピーV3（マスターV3) |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | 33.3% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 2 months** | Every 38 months |
| Monetization | Free | — |
| Size | 265 MB | 15 MB |
| Requires iOS | 15.0 | **12.0** |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [iBODY.,LTD (Tokyo)](https://appshunter.io/developer/1142049521) | [A-JOHO SERVICE K.K.](https://appshunter.io/developer/1449736062) |

## What reviewers say

### i

[App page](https://appshunter.io/ios/app/i-body/id1142049522)

Visualize your body's composition and shape in 3D using data from a body scanner and composition analyzer. Examine fat, muscle, and bone structure layer by layer, and track your physical changes over time with side-by-side 3D comparisons.

**Highlights:** 3D body visualization, Body composition analysis, Fat, muscle, and bone reference, Numerical body size data, Historical body change comparison

**In-app purchases:** none


### 脊椎セラピーV3（マスターV3)

[App page](https://appshunter.io/ios/app/v3v3/id1449736063)

**In-app purchases:** none


## Frequently asked questions

### Is i free?

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

### Is 脊椎セラピーV3（マスターV3) free?

脊椎セラピーV3（マスターV3) is free to download, with no in-app purchases.

### Do i or 脊椎セラピーV3（マスターV3) have ads?

Neither i nor 脊椎セラピーV3（マスターV3) shows ads.

### Which is updated more often, i or 脊椎セラピーV3（マスターV3)?

i ships an update every 2 months, and 脊椎セラピーV3（マスターV3) every 38 months. Most recently, i was updated on October 10, 2026 and 脊椎セラピーV3（マスターV3) on October 26, 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.*