# Diet Lights vs Yakusoku.

The clearest difference is in-app purchases: Yakusoku. at none against Diet Lights's 3. Yakusoku. also leads on ads (none vs shown) and update cadence (weekly vs every 2 weeks). Diet Lights's advantage is device support (3 vs 1) and iOS requirement (15.1 vs 17.0). On price there is nothing between them.

Both are free to download. Diet Lights sells 3 in-app purchases, starting at $1.99 per 7 days. Yakusoku. asks for nothing beyond the download.

Diet Lights ships an update every 2 weeks, Yakusoku. weekly. The most recent releases landed on November 6, 2026 and October 31, 2026 respectively.

## The numbers

| Metric | Diet Lights | Yakusoku. |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.5 (2 ratings)](https://appshunter.io/ios/app/diet-lights-weight-tracker/id6748281990/reviews)** | — |
| Number of ratings | **2** | — |
| Positive reviews | 83.3% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | Every 2 weeks | **Weekly** |
| Monetization | Free with in-app purchases | — |
| Size | 94 MB | 1 MB |
| Requires iOS | **15.1** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [House201](https://appshunter.io/developer/1767211373) | [Shosuke Sato](https://appshunter.io/developer/1709991841) |

## What reviewers say

### Diet Lights

[App page](https://appshunter.io/ios/app/diet-lights-weight-tracker/id6748281990)

This app helps you track your weight and diet progress using a simple traffic light system. It allows you to log morning and evening weights, monitor trends, and record daily factors like mood and meals.

**Highlights:** Traffic light weight progress system, Morning and evening weight logging, Weight trend graphs, Calendar view of daily progress, Intermittent fasting timer, Mood and meal logging, BMI calculation

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 프리미엄 | $1.99 | per 7 days |
| Premium Monthly | $2.99 | per month |
| Premium | $12.99 | per year |


### Yakusoku.

[App page](https://appshunter.io/ios/app/yakusoku/id6762287005)

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

**In-app purchases:** none


## Frequently asked questions

### Is Diet Lights free?

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

### Is Yakusoku. free?

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

### Do Diet Lights or Yakusoku. have ads?

Diet Lights shows ads; Yakusoku. does not.

### Which is updated more often, Diet Lights or Yakusoku.?

Diet Lights ships an update every 2 weeks, and Yakusoku. weekly. Most recently, Diet Lights was updated on November 6, 2026 and Yakusoku. on October 31, 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.*