# Calcium vs Hydroo

The clearest difference is in-app purchases: Hydroo at none against Calcium's 3. Hydroo also leads on ads (none vs shown) and update cadence (fortnightly vs every 7 months). Calcium's advantage is device support (3 vs 1) and iOS requirement (15.0 vs 17.0). On price there is nothing between them.

Both are free to download. Calcium sells 3 in-app purchases, starting at $4.99 per month. Hydroo asks for nothing beyond the download.

Calcium ships an update every 7 months, Hydroo fortnightly. The most recent releases landed on November 3, 2026 and November 8, 2026 respectively.

## The numbers

| Metric | Calcium | Hydroo |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (2 ratings)](https://appshunter.io/ios/app/calcium-ai-powered/id1631181354/reviews)** | — |
| Number of ratings | **2** | — |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | Every 7 months | **Fortnightly** |
| Monetization | Free with in-app purchases | — |
| Size | 52 MB | 23 MB |
| Requires iOS | **15.0** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Two Platforms Inc.](https://appshunter.io/developer/1589333017) | [Khawlah Bawazir](https://appshunter.io/developer/1627702695) |

## What reviewers say

### Calcium

[App page](https://appshunter.io/ios/app/calcium-ai-powered/id1631181354)

This app provides daily motivational quotes generated by AI to help users overcome anxiety and negative thoughts. It encourages positive growth and resilience in the face of life's challenges. Users can receive one quote for free or upgrade for more.

**Highlights:** AI-generated motivational quotes, Daily inspirational messages, Positive mindset encouragement, Overcome anxiety and worries, Premium upgrade for more quotes

**Features:** macOS Compatibility

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Premium Subscription (1 Month) | $4.99 | per month |
| Premium Subscription (1 Year) | $29.99 | per year |
| Quote for the day | $0.99 | one-time |


### Hydroo

[App page](https://appshunter.io/ios/app/hydroo/id6504790565)

**In-app purchases:** none


## Frequently asked questions

### Is Calcium free?

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

### Is Hydroo free?

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

### Do Calcium or Hydroo have ads?

Calcium shows ads; Hydroo does not.

### Which is updated more often, Calcium or Hydroo?

Calcium ships an update every 7 months, and Hydroo fortnightly. Most recently, Calcium was updated on November 3, 2026 and Hydroo on November 8, 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.*