# Data Rhythm vs Dian Dian

The clearest difference is in-app purchases: Data Rhythm at none against Dian Dian's 3. Dian Dian's advantage is update cadence (every 5 days vs every 3 weeks) and device support (3 vs 1). On price, ads and iOS requirement there is nothing between them.

Both are free to download. Dian Dian sells 3 in-app purchases, starting at $1.99 per month. Data Rhythm asks for nothing beyond the download.

Data Rhythm ships an update every 3 weeks, Dian Dian every 5 days. The most recent releases landed on October 27, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | Data Rhythm | Dian Dian |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | Yes | Yes |
| Update frequency | Every 3 weeks | **Every 5 days** |
| Size | 17 MB | 65 MB |
| Requires iOS | 16.6 | **15.0** |
| Devices | iPhone | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Masaki Hayashi](https://appshunter.io/developer/1609931545) | [Override SAS](https://appshunter.io/developer/1888186144) |

## What reviewers say

### Data Rhythm

[App page](https://appshunter.io/ios/app/data-rhythm/id1639696025)

**Features:** macOS Compatibility

**In-app purchases:** none


### Dian Dian

[App page](https://appshunter.io/ios/app/dian-dian-year-tracker/id6761432329)

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Premium Monthly | $1.99 | per month |
| Premium Yearly | $8.99 | per year |
| Premium Lifetime | $22.99 | one-time |


## Frequently asked questions

### Is Data Rhythm free?

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

### Is Dian Dian free?

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

### Do Data Rhythm or Dian Dian have ads?

Both Data Rhythm and Dian Dian show ads.

### Which is updated more often, Data Rhythm or Dian Dian?

Data Rhythm ships an update every 3 weeks, and Dian Dian every 5 days. Most recently, Data Rhythm was updated on October 27, 2026 and Dian Dian on October 25, 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.*