# Sun Day Tracker vs The90 Gem

The clearest difference is rating: Sun Day Tracker at 4.6 against The90 Gem's 4.3. Sun Day Tracker also leads on ratings volume (26 vs 7). The90 Gem's advantage is iOS requirement (15.0 vs 17.0). On price, review sentiment, update cadence and ads there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Sun Day Tracker holds the better App Store score, 4.6 against 4.3. Both are backed by a comparable volume of ratings — 26 and 7 respectively. Written reviews point the same way: 83% of Sun Day Tracker's written reviews are positive against 80% of The90 Gem's.

Sun Day Tracker ships an update monthly, The90 Gem every 2 weeks. The most recent releases landed on October 17, 2026 and October 5, 2026 respectively.

## The numbers

| Metric | Sun Day Tracker | The90 Gem |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.6 (26 ratings)](https://appshunter.io/ios/app/sun-day-tracker/id6748545544/reviews)** | [4.3 (7 ratings)](https://appshunter.io/ios/app/the90-gem/id6758100822/reviews) |
| Number of ratings | **26** | 7 |
| Positive reviews | **83.3% of reviews** | 80.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Monthly | **Every 2 weeks** |
| Monetization | Free | Free |
| Size | 1 MB | 96 MB |
| Requires iOS | 17.0 | **15.0** |
| Devices | iPhone | **iPhone, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [permissionless tech, llc](https://appshunter.io/developer/1824145893) | [The90, Inc.](https://appshunter.io/developer/1870863367) |

## What reviewers say

### Sun Day Tracker

[App page](https://appshunter.io/ios/app/sun-day-tracker/id6748545544)

Monitor your daily vitamin D absorption from sunlight exposure. This straightforward application helps you keep track of your sun-related vitamin D intake.

**Highlights:** Track daily vitamin D intake, Sunlight exposure monitoring, Simple interface, Daily tracking

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

**In-app purchases:** none


### The90 Gem

[App page](https://appshunter.io/ios/app/the90-gem/id6758100822)

This jewelry-inspired sensor tracks your skin's real-time UV exposure. It helps you protect against aging and harness the sun's health benefits.

**Highlights:** Real-time UV tracking, Skin exposure monitoring, Aging protection, Sun health benefits, Jewelry-inspired design

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

**In-app purchases:** none


## Frequently asked questions

### Is Sun Day Tracker free?

Sun Day Tracker is free to download, with no in-app purchases.

### Is The90 Gem free?

The90 Gem is free to download, with no in-app purchases.

### Which has better reviews, Sun Day Tracker or The90 Gem?

Sun Day Tracker is rated higher. Sun Day Tracker averages 4.6 out of 5 from 26 ratings, while The90 Gem averages 4.3 from 7 ratings.

### Do Sun Day Tracker or The90 Gem have ads?

Neither Sun Day Tracker nor The90 Gem shows ads.

### Which is updated more often, Sun Day Tracker or The90 Gem?

Sun Day Tracker ships an update monthly, and The90 Gem every 2 weeks. Most recently, Sun Day Tracker was updated on October 17, 2026 and The90 Gem on October 5, 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.*