# FFMI Calc vs Diet Otter . Weight Tracker

The clearest difference is ads: FFMI Calc at none against Diet Otter . Weight Tracker's shown. FFMI Calc also leads on update cadence (every 5 days vs every 3 weeks). Diet Otter . Weight Tracker's advantage is iOS requirement (17.0 vs 26.4). On price, 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.

FFMI Calc ships an update every 5 days, Diet Otter . Weight Tracker every 3 weeks. The most recent releases landed on October 28, 2026 and November 5, 2026 respectively.

## The numbers

| Metric | FFMI Calc | Diet Otter . Weight Tracker |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | **No** | Yes |
| Update frequency | **Every 5 days** | Every 3 weeks |
| Size | 1 MB | 7 MB |
| Requires iOS | 26.4 | **17.0** |
| Devices | **iPhone, iPad** | iPhone |
| Age rating | 4+ | 12+ |
| Developer | [Tomoharu Iseki](https://appshunter.io/developer/1863683948) | [simon Depussay](https://appshunter.io/developer/1729550168) |

## What reviewers say

### FFMI Calc

[App page](https://appshunter.io/ios/app/ffmi-calc/id6768256805)

**Features:** macOS Compatibility

**In-app purchases:** none


### Diet Otter . Weight Tracker

[App page](https://appshunter.io/ios/app/diet-otter-weight-tracker/id6770398324)

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

**In-app purchases:** none


## Frequently asked questions

### Is FFMI Calc free?

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

### Is Diet Otter . Weight Tracker free?

Diet Otter . Weight Tracker is free to download, with no in-app purchases.

### Do FFMI Calc or Diet Otter . Weight Tracker have ads?

Diet Otter . Weight Tracker shows ads; FFMI Calc does not.

### Which is updated more often, FFMI Calc or Diet Otter . Weight Tracker?

FFMI Calc ships an update every 5 days, and Diet Otter . Weight Tracker every 3 weeks. Most recently, FFMI Calc was updated on October 28, 2026 and Diet Otter . Weight Tracker on November 5, 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.*