# HYDROS App vs Reef Buddy

The clearest difference is rating: Reef Buddy at 3.9 against HYDROS App's 3.4. Reef Buddy also leads on update cadence (fortnightly vs every 3 months). HYDROS App's advantage is in-app purchases (none vs 4) and iOS requirement (15.6 vs 26.0). On price, review sentiment, ratings volume and ads there is nothing between them.

Both are free to download. Reef Buddy sells 4 in-app purchases, starting at $0.99 per 7 days. HYDROS App asks for nothing beyond the download.

Reef Buddy holds the better App Store score, 3.9 against 3.4. Both are backed by a comparable volume of ratings — 25 and 20 respectively. Written reviews complicate that: 62% of HYDROS App's written reviews are positive against 55% of Reef Buddy's, so the app with the better star average is not the one people write more warmly about.

HYDROS App ships an update every 3 months, Reef Buddy fortnightly. The most recent releases landed on November 6, 2026 and November 3, 2026 respectively.

## The numbers

| Metric | HYDROS App | Reef Buddy |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [3.4 (25 ratings)](https://appshunter.io/ios/app/hydros-app/id1455344294/reviews) | **[3.9 (20 ratings)](https://appshunter.io/ios/app/reef-buddy-reef-tank-tracker/id1593580822/reviews)** |
| Number of ratings | **25** | 20 |
| Positive reviews | **62.3% of reviews** | 54.5% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 3 months | **Fortnightly** |
| Monetization | **Free** | Freemium |
| Size | 70 MB | 46 MB |
| Requires iOS | **15.6** | 26.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, Mac |
| Age rating | 4+ | 4+ |
| Developer | [Coralvue](https://appshunter.io/developer/1455344293) | [maxime marinel](https://appshunter.io/developer/595076846) |

## What reviewers say

### HYDROS App

[App page](https://appshunter.io/ios/app/hydros-app/id1455344294)

Easily monitor and control your aquarium's vital parameters like temperature, pH, and salinity. Manage all your connected devices, including ATOs, lights, and pumps, with a user-friendly interface. Quick setup with preset configurations means no coding is required to get your system running.

**Highlights:** Monitor temperature, ORP, pH, salinity, Control ATO, lights, heaters, pumps, User-friendly interface, Quick setup with presets, Manage multiple devices and aquariums, Set schedules and create modes

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

**In-app purchases:** none


### Reef Buddy

[App page](https://appshunter.io/ios/app/reef-buddy-reef-tank-tracker/id1593580822)

Easily log, monitor, and analyze your saltwater aquarium's critical parameters. Get smart insights and personalized advice to maintain a healthy reef tank. Syncs across devices and offers guidance for manual test results.

**Highlights:** Log critical aquarium parameters, Monitor KH, salinity, pH, Ca, Mg, and more, Analyze data with automated insights, Sync data across iPhone and iPad, Guidance for manual test kit results, Personalized advice with premium subscription

**Features:** Vision Pro support

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Reef Buddy Pro Weekly | $0.99 | per 7 days |
| Reef Buddy Pro | $1.99 | per month |
| Reef buddy pro month | $3.99 | per month |
| Reef buddy pro annual | $44.99 | per year |


## Frequently asked questions

### Is HYDROS App free?

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

### Is Reef Buddy free?

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

### Which has better reviews, HYDROS App or Reef Buddy?

Reef Buddy is rated higher. HYDROS App averages 3.4 out of 5 from 25 ratings, while Reef Buddy averages 3.9 from 20 ratings.

### Do HYDROS App or Reef Buddy have ads?

Neither HYDROS App nor Reef Buddy shows ads.

### Which is updated more often, HYDROS App or Reef Buddy?

HYDROS App ships an update every 3 months, and Reef Buddy fortnightly. Most recently, HYDROS App was updated on November 6, 2026 and Reef Buddy on November 3, 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.*