# SunDose! vs Zero

The clearest difference is update cadence: SunDose! at every 4 days against Zero's every 3 weeks. SunDose! also leads on ratings volume (4 vs 1) and iOS requirement (15.1 vs 18.5). On price, rating, ads and in-app purchases there is nothing between them.

Both are free to download. SunDose! sells 3 in-app purchases, starting at $2.99 per month and Zero sells 3 in-app purchases, starting at $1.99 per month. Whichever you choose, the download price is not the number that matters.

On the App Store both sit at effectively the same score — 5.0 for SunDose! against 5.0 for Zero. Both are backed by a comparable volume of ratings — 4 and 1 respectively.

SunDose! ships an update every 4 days, Zero every 3 weeks. The most recent releases landed on October 7, 2026 and October 16, 2026 respectively.

## The numbers

| Metric | SunDose! | Zero |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [5.0 (4 ratings)](https://appshunter.io/ios/app/sundose/id6742912257/reviews) | [5.0 (1 ratings)](https://appshunter.io/ios/app/zero-rush/id6753113382/reviews) |
| Number of ratings | **4** | 1 |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | **Every 4 days** | Every 3 weeks |
| Monetization | Freemium | Freemium |
| Size | 37 MB | 10 MB |
| Requires iOS | **15.1** | 18.5 |
| Devices | **iPhone, iPad, iPod** | iPhone, Apple Watch |
| Age rating | 17+ | 4+ |
| Developer | [Prispa Solutions LLC](https://appshunter.io/developer/1800557753) | [Carlos Adiel Vega Lopez](https://appshunter.io/developer/1842567782) |

## What reviewers say

### SunDose!

[App page](https://appshunter.io/ios/app/sundose/id6742912257)

This app helps you establish a consistent morning sunlight habit to improve sleep, mood, and energy. It offers personalized goals, streak tracking, and educational content, with premium features for advanced health metrics and AI insights.

**Highlights:** Personalized daily sunlight goals, Streak tracking for consistency, Detailed progress visualization, Educational content on sunlight benefits, Reminders for habit maintenance, Vitamin D and sleep optimization tracking

**Features:** macOS Compatibility

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Unlimited access | $2.99 | per month |
| Unlimited access | $29.99 | per year |
| Unlimited access | $69.99 | one-time |


### Zero

[App page](https://appshunter.io/ios/app/zero-rush/id6753113382)

This app helps you manage stress by combining guided breathing exercises with real-time biometric data from your Apple Watch. It provides insights into your stress patterns and helps you schedule recovery moments to build resilience.

**Highlights:** Guided breathing exercises, Real-time biometric tracking (RHR, HRV), Stress pattern analysis, Scheduled mindful breaks, Relaxation validation, Local data storage

**Features:** Apple Watch app

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| All Access – Monthly | $1.99 | per month |
| All Access – Yearly | $19.99 | per year |
| Lifetime All Access | $89.99 | one-time |


## Frequently asked questions

### Is SunDose! free?

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

### Is Zero free?

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

### Which has better reviews, SunDose! or Zero?

SunDose! and Zero are both rated 5.0 out of 5 on the App Store, from 4 and 1 ratings respectively.

### Do SunDose! or Zero have ads?

Neither SunDose! nor Zero shows ads.

### Which is updated more often, SunDose! or Zero?

SunDose! ships an update every 4 days, and Zero every 3 weeks. Most recently, SunDose! was updated on October 7, 2026 and Zero on October 16, 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.*