# Sigma vs 吃有数

The clearest difference is rating: 吃有数 at 5.0 against Sigma's 4.4. 吃有数 also leads on review sentiment (98% vs 87%). Sigma's advantage is in-app purchases (none vs 6) and ratings volume (54 vs 2). On price, update cadence, ads and monetization model there is nothing between them.

Both are free to download. 吃有数 sells 6 one-off in-app purchases. Sigma asks for nothing beyond the download.

吃有数 holds the better App Store score, 5.0 against 4.4. That said, the two scores are not equally well evidenced: Sigma has 54 ratings behind it against 2, so its average is the more settled of the two. Written reviews point the same way: 87% of Sigma's written reviews are positive against 98% of 吃有数's.

Both ship on a similar rhythm, roughly weekly. The most recent releases landed on October 20, 2026 and October 18, 2026 respectively.

## The numbers

| Metric | Sigma | 吃有数 |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.4 (54 ratings)](https://appshunter.io/ios/app/sigma-ai/id6743433033/reviews) | **[5.0 (2 ratings)](https://appshunter.io/ios/app/ai/id6756397162/reviews)** |
| Number of ratings | **54** | 2 |
| Positive reviews | 86.8% of reviews | **97.6% of reviews** |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Weekly | Weekly |
| Monetization | Free | Free |
| Size | 231 MB | 96 MB |
| Requires iOS | **14.0** | 15.5 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 12+ | 4+ |
| Developer | [Chaoshi Technology (Shanghai) Co., Ltd.](https://appshunter.io/developer/1520053656) | [明 程](https://appshunter.io/developer/1055905153) |

## What reviewers say

### Sigma

[App page](https://appshunter.io/ios/app/sigma-ai/id6743433033)

This app offers a clean and engaging running experience with detailed analysis and personalized AI coaching. Track your runs, visualize your progress, and collect memories of your journeys on a unique map diary.

**Highlights:** Ad-free running experience, Daily, weekly, and monthly analysis, Map diary of runs and moods, AI-powered personalized coaching, Visualized calorie consumption, Data migration from popular wearables

**In-app purchases:** none


### 吃有数

[App page](https://appshunter.io/ios/app/ai/id6756397162)

This AI-powered app simplifies calorie and nutrition tracking with photo recognition. It helps users set personalized weight loss goals, monitor progress with data visualization, and manage their diet and exercise for a healthier lifestyle.

**Highlights:** AI food recognition via photo, Automatic calorie and nutrition calculation, Personalized daily calorie goals, Detailed nutrition analysis, Weight and BMI tracking, Exercise calorie compensation, Progress photo tracking

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

**In-app purchases (6)**

| Purchase | Price | Billing |
| --- | --- | --- |
| CalShot-15天会员 | $0.99 | one-time |
| CalShot-30天会员 | $2.99 | one-time |
| 180天会员特价 | $4.99 | one-time |
| 一年会员特价 | $9.99 | one-time |
| 2年会员特价 | $14.99 | one-time |
| 永久会员 | $19.99 | one-time |


## Frequently asked questions

### Is Sigma free?

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

### Is 吃有数 free?

吃有数 is free to download, with in-app purchases available.

### Which has better reviews, Sigma or 吃有数?

吃有数 is rated higher. Sigma averages 4.4 out of 5 from 54 ratings, while 吃有数 averages 5.0 from 2 ratings.

### Do Sigma or 吃有数 have ads?

Neither Sigma nor 吃有数 shows ads.

### Which is updated more often, Sigma or 吃有数?

Sigma ships an update weekly, and 吃有数 weekly. Most recently, Sigma was updated on October 20, 2026 and 吃有数 on October 18, 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.*