# SunDose vs RayDay

The clearest difference is ads: RayDay at none against SunDose's shown. RayDay also leads on iOS requirement (17.0 vs 26.0). SunDose's advantage is update cadence (every 4 days vs every 3 weeks). On price, in-app purchases and device support there is nothing between them.

Both are free to download. SunDose sells 2 in-app purchases, starting at $1.99 per 7 days and RayDay sells 3 in-app purchases, starting at $4.99 per 7 days. Whichever you choose, the download price is not the number that matters.

SunDose ships an update every 4 days, RayDay every 3 weeks. The most recent releases landed on November 5, 2026 and October 31, 2026 respectively.

## The numbers

| Metric | SunDose | RayDay |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[3.0 (2 ratings)](https://appshunter.io/ios/app/rayday-vitamin-d-tracker/id6761286896/reviews)** |
| Number of ratings | — | **2** |
| In-app purchases | Yes | Yes |
| Ads | Yes | **No** |
| Update frequency | **Every 4 days** | Every 3 weeks |
| Monetization | — | Freemium |
| Size | 72 MB | 26 MB |
| Requires iOS | 26.0 | **17.0** |
| Devices | iPhone | **iPhone, iPad** |
| Age rating | 17+ | 4+ |
| Developer | [nebahat akpolat](https://appshunter.io/developer/1818080751) | [Jakub Laszczyk](https://appshunter.io/developer/568719342) |

## What reviewers say

### SunDose

[App page](https://appshunter.io/ios/app/sundose/id6759666436)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Sundose Premium | $1.99 | per 7 days |
| Sundose Premium | $4.99 | per month |


### RayDay

[App page](https://appshunter.io/ios/app/rayday-vitamin-d-tracker/id6761286896)

This app helps you understand your daily window for natural Vitamin D production. It calculates optimal sun exposure times based on your location and skin type, providing forecasts and real-time atmospheric data.

**Highlights:** D-Window Calculator, Live Solar Path animation, 7-Day D-Window Forecast, Skin Type Personalization, Smart Notifications, Real-time Atmospheric Data, Home Screen Widget

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| RayDay Weekly | $4.99 | per 7 days |
| RayDay Yearly | $24.99 | per year |
| Early Supporter Yearly | $24.99 | per year |


## Frequently asked questions

### Is SunDose free?

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

### Is RayDay free?

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

### Do SunDose or RayDay have ads?

SunDose shows ads; RayDay does not.

### Which is updated more often, SunDose or RayDay?

SunDose ships an update every 4 days, and RayDay every 3 weeks. Most recently, SunDose was updated on November 5, 2026 and RayDay on October 31, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*