# Sunbathe vs Hydro Track

The clearest difference is in-app purchases: Hydro Track at none against Sunbathe's 1. Sunbathe's advantage is update cadence (every 3 weeks vs every 2 months). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. Sunbathe sells 1 in-app purchase, starting at $3.99 per month. Hydro Track asks for nothing beyond the download.

Sunbathe ships an update every 3 weeks, Hydro Track every 2 months. The most recent releases landed on October 7, 2026 and September 30, 2026 respectively.

## The numbers

| Metric | Sunbathe | Hydro Track |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Every 3 weeks** | Every 2 months |
| Monetization | Freemium | — |
| Size | 43 MB | 22 MB |
| Requires iOS | **15.1** | 15.6 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Julia Alvarez de Eulate Sainz](https://appshunter.io/developer/1662471073) | [OKAN COSKUN](https://appshunter.io/developer/6779292439) |

## What reviewers say

### Sunbathe

[App page](https://appshunter.io/ios/app/sunbathe/id6449760948)

This app helps you understand your vitamin D needs and how to get enough through safe sun exposure. It calculates optimal sunning times and duration based on your location to prevent deficiency and related health issues.

**Highlights:** Vitamin D deficiency information, Optimal sun exposure timing, Personalized duration calculations, Location-based recommendations, Health benefit insights

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Sunbathe Premium | $3.99 | per month |


### Hydro Track

[App page](https://appshunter.io/ios/app/hydro-track-never-forget/id6779292437)

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

**In-app purchases:** none


## Frequently asked questions

### Is Sunbathe free?

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

### Is Hydro Track free?

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

### Do Sunbathe or Hydro Track have ads?

Neither Sunbathe nor Hydro Track shows ads.

### Which is updated more often, Sunbathe or Hydro Track?

Sunbathe ships an update every 3 weeks, and Hydro Track every 2 months. Most recently, Sunbathe was updated on October 7, 2026 and Hydro Track on September 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.*