# SmileDiary vs 22 Hours

The clearest difference is in-app purchases: 22 Hours at none against SmileDiary's 3. SmileDiary's advantage is update cadence (every 5 days vs every 6 weeks). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. SmileDiary sells 3 in-app purchases, starting at $2.99 per month. 22 Hours asks for nothing beyond the download.

SmileDiary ships an update every 5 days, 22 Hours every 6 weeks. The most recent releases landed on September 22, 2026 and September 23, 2026 respectively.

## The numbers

| Metric | SmileDiary | 22 Hours |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[3.7 (3 ratings)](https://appshunter.io/ios/app/22-hours-aligner-tracker/id6764899476/reviews)** |
| Number of ratings | — | **3** |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Every 5 days** | Every 6 weeks |
| Monetization | Freemium | **Free** |
| Size | 12 MB | 12 MB |
| Requires iOS | 17.0 | 17.0 |
| Devices | iPhone, Apple Watch | **iPhone, iPad, Apple Watch** |
| Age rating | 4+ | 4+ |
| Developer | [Nanjing Xiaowei Technology Co., Ltd.](https://appshunter.io/developer/1831757763) | [Gazewing LLC](https://appshunter.io/developer/1895955102) |

## What reviewers say

### SmileDiary

[App page](https://appshunter.io/ios/app/smilediary-aligner-tracker/id6753011249)

This app helps you track your clear aligner treatment privately and securely. It offers a smart wear timer, visual calendar, progress photos, and detailed insights into your compliance, all without collecting your personal data.

**Highlights:** Private data storage, No registration required, Smart wear timer, Visual compliance calendar, Guided progress photos, Detailed treatment insights, Data export functionality

**Features:** macOS Compatibility, Apple Watch app, Vision Pro support

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| SmileDiary Pro Monthly | $2.99 | per month |
| SmileDiary Pro Annual | $12.99 | per year |
| SmileDiary Pro Lifetime | $19.99 | one-time |


### 22 Hours

[App page](https://appshunter.io/ios/app/22-hours-aligner-tracker/id6764899476)

This app helps users track their clear aligner wear time accurately. It provides simple one-tap logging for aligner insertion and removal, offering insights into daily progress, streaks, and treatment history. The app also includes helpful reminders and progress photo capabilities.

**Highlights:** One-tap aligner wear logging, Daily out-time budget visualization, Streak tracking for goal achievement, Detailed stats and treatment history, Customizable reminders for aligner changes, Progress photo capture and management, Siri integration for hands-free logging

**Features:** macOS Compatibility, Apple Watch app, Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is SmileDiary free?

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

### Is 22 Hours free?

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

### Do SmileDiary or 22 Hours have ads?

Neither SmileDiary nor 22 Hours shows ads.

### Which is updated more often, SmileDiary or 22 Hours?

SmileDiary ships an update every 5 days, and 22 Hours every 6 weeks. Most recently, SmileDiary was updated on September 22, 2026 and 22 Hours on September 23, 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.*