# Hydrated Pass vs Oyster Identification

The clearest difference is in-app purchases: Oyster Identification at none against Hydrated Pass's 1. Hydrated Pass's advantage is update cadence (every 10 days vs every 4 weeks) and iOS requirement (15.1 vs 18.0). On price, ads and device support there is nothing between them.

Both are free to download. Hydrated Pass sells 1 in-app purchase, starting at $19.99 per month. Oyster Identification asks for nothing beyond the download.

Hydrated Pass ships an update every 10 days, Oyster Identification every 4 weeks. Both last shipped on October 30, 2026.

## The numbers

| Metric | Hydrated Pass | Oyster Identification |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Every 10 days** | Every 4 weeks |
| Size | 51 MB | 13 MB |
| Requires iOS | **15.1** | 18.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Hydrated Company](https://appshunter.io/developer/1772018483) | [Henry Heleine](https://appshunter.io/developer/797164760) |

## What reviewers say

### Hydrated Pass

[App page](https://appshunter.io/ios/app/hydrated-pass-merchant/id6736438846)

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| HPM premium | $19.99 | per month |


### Oyster Identification

[App page](https://appshunter.io/ios/app/oyster-identification/id6743009625)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Hydrated Pass free?

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

### Is Oyster Identification free?

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

### Do Hydrated Pass or Oyster Identification have ads?

Neither Hydrated Pass nor Oyster Identification shows ads.

### Which is updated more often, Hydrated Pass or Oyster Identification?

Hydrated Pass ships an update every 10 days, and Oyster Identification every 4 weeks. Most recently, Hydrated Pass was updated on October 30, 2026 and Oyster Identification on October 30, 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.*