# D vs Allergy Diary

The clearest difference is update cadence: Allergy Diary at daily against D's every 5 days. Allergy Diary also leads on iOS requirement (13.0 vs 15.0). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

D ships an update every 5 days, Allergy Diary daily. Both last shipped on November 5, 2026.

## The numbers

| Metric | D | Allergy Diary |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 5 days | **Daily** |
| Size | 43 MB | 35 MB |
| Requires iOS | 15.0 | **13.0** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [LUN LIU](https://appshunter.io/developer/1890125123) | [HeungYeol Kim](https://appshunter.io/developer/1878087341) |

## What reviewers say

### D

[App page](https://appshunter.io/ios/app/d-sync-ecu/id6761677479)

**Features:** iPhone Duo support

**In-app purchases:** none


### Allergy Diary

[App page](https://appshunter.io/ios/app/allergy-diary-symptom-log/id6762033562)

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

**In-app purchases:** none


## Frequently asked questions

### Is D free?

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

### Is Allergy Diary free?

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

### Do D or Allergy Diary have ads?

Neither D nor Allergy Diary shows ads.

### Which is updated more often, D or Allergy Diary?

D ships an update every 5 days, and Allergy Diary daily. Most recently, D was updated on November 5, 2026 and Allergy Diary on November 5, 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.*