# Fast AI vs 16

The clearest difference is review sentiment: 16 at 100% against Fast AI's 7%. Fast AI's advantage is ads (none vs shown) and rating (4.3 vs 4.0). On price, in-app purchases, monetization model and device support there is nothing between them.

Both are free to download. Fast AI sells 5 in-app purchases, starting at $5.99 per 7 days and 16 sells 5 in-app purchases, starting at $4.99 per 7 days. Whichever you choose, the download price is not the number that matters.

Fast AI holds the better App Store score, 4.3 against 4.0. That said, the two scores are not equally well evidenced: Fast AI has 120 ratings behind it against 4, so its average is the more settled of the two. Written reviews complicate that: 7% of Fast AI's written reviews are positive against 100% of 16's, so the app with the better star average is not the one people write more warmly about.

Fast AI ships an update every 2 weeks, 16 every 6 weeks. Both last shipped on November 3, 2026.

## The numbers

| Metric | Fast AI | 16 |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.3 (120 ratings)](https://appshunter.io/ios/app/fast-ai-intermittent-fasting/id1629661646/reviews)** | [4.0 (4 ratings)](https://appshunter.io/ios/app/168-fasting-timer/id6449992745/reviews) |
| Number of ratings | **120** | 4 |
| Positive reviews | 7.1% of reviews | **100.0% of reviews** |
| In-app purchases | Yes | Yes |
| Ads | **No** | Yes |
| Update frequency | **Every 2 weeks** | Every 6 weeks |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Size | 101 MB | 54 MB |
| Requires iOS | 14.0 | **13.0** |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 17+ |
| Developer | [Kiryl Salavei](https://appshunter.io/developer/1033680093) | [Maple Labs Co., Ltd](https://appshunter.io/developer/1320450180) |

## What reviewers say

### Fast AI

[App page](https://appshunter.io/ios/app/fast-ai-intermittent-fasting/id1629661646)

This app helps users achieve weight loss and improve well-being through intermittent fasting. It provides tracking, scheduling, and detailed analytics to guide users through various fasting plans. The app aims to make fasting a natural and effective part of a healthy lifestyle.

**Highlights:** Intermittent fasting tracker, Weight monitoring, Fasting and food window notifications, Detailed analytics, Multiple fasting schemes (e.g., 16/8), Fasting schedule, Apple Health weight sync

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

**In-app purchases (5)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Simple intermittent fasting | $5.99 | per 7 days |
| Intermittent Fasting 1 Month | $12.99 | per month |
| Personal Fast Program 3 Month | $19.99 | per 3 months |
| Intermittent Fasting + Tracker | $35.99 | per year |
| Intermittent Fasting Annual | $49.99 | per year |


### 16

[App page](https://appshunter.io/ios/app/168-fasting-timer/id6449992745)

Track your intermittent fasting journey with customizable plans and real-time analytics. Log meals and water intake, and receive personalized meal tips to support your weight loss goals. Supports various popular fasting methods.

**Highlights:** Intermittent fasting timer, Custom fasting plans, Real-time analytics, Meal and water tracker, Meal tips and recipes, Multiple fasting modes

**Features:** macOS Compatibility

**In-app purchases (5)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Weekly Premium | $4.99 | per 7 days |
| Monthly Premium | $9.99 | per month |
| Yearly Premium | $12.99 | per year |
| Premium | $12.99 | per 3 months |
| Premium | $24.99 | per 3 months |


## Frequently asked questions

### Is Fast AI free?

Fast AI is free to download, with in-app purchases available.

### Is 16 free?

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

### Which has better reviews, Fast AI or 16?

Fast AI is rated higher. Fast AI averages 4.3 out of 5 from 120 ratings, while 16 averages 4.0 from 4 ratings.

### Do Fast AI or 16 have ads?

16 shows ads; Fast AI does not.

### Which is updated more often, Fast AI or 16?

Fast AI ships an update every 2 weeks, and 16 every 6 weeks. Most recently, Fast AI was updated on November 3, 2026 and 16 on November 3, 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.*