# G21 vs Sunlighten

The clearest difference is rating: G21 at 3.7 against Sunlighten's 2.7. G21 also leads on update cadence (monthly vs every 4 months). Sunlighten's advantage is ads (none vs shown) and ratings volume (84 vs 3). On price, in-app purchases, device support and iOS requirement there is nothing between them.

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

G21 holds the better App Store score, 3.7 against 2.7. That said, the two scores are not equally well evidenced: Sunlighten has 84 ratings behind it against 3, so its average is the more settled of the two.

G21 ships an update monthly, Sunlighten every 4 months. The most recent releases landed on October 15, 2026 and October 30, 2026 respectively.

## The numbers

| Metric | G21 | Sunlighten |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[3.7 (3 ratings)](https://appshunter.io/ios/app/g21/id1211311329/reviews)** | [2.7 (84 ratings)](https://appshunter.io/ios/app/sunlighten/id1634410434/reviews) |
| Number of ratings | 3 | **84** |
| Positive reviews | — | 19.8% of reviews |
| In-app purchases | No | No |
| Ads | Yes | **No** |
| Update frequency | **Monthly** | Every 4 months |
| Monetization | Ad-supported | **Free** |
| Size | 152 MB | 53 MB |
| Requires iOS | **14.0** | 15.1 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 17+ |
| Developer | [Gravity 21 Fort Lauderdale, LLC](https://appshunter.io/developer/1821273003) | [Sunlighten Inc](https://appshunter.io/developer/1634410436) |

## What reviewers say

### G21

[App page](https://appshunter.io/ios/app/g21/id1211311329)

Easily plan and schedule your fitness classes directly from your mobile device. View class schedules, sign up for sessions, and access studio location information. Optimize your time and enjoy the convenience of managing your fitness activities on the go.

**Highlights:** View class schedules, Sign up for classes, Access studio location information, Optimize time management, Convenient mobile access

**Features:** macOS Compatibility, Apple Wallet

**In-app purchases:** none


### Sunlighten

[App page](https://appshunter.io/ios/app/sunlighten/id1634410434)

Optimize your well-being with this app, designed to enhance your light therapy and sauna experiences. Create personalized wellness programs, track sessions in real-time, and control your devices remotely for a seamless health journey.

**Highlights:** Science-based wellness programs, Personalized program creation, Real-time session tracking, Remote sauna control (Wi-Fi), Audio and lighting management, Red light therapy panel programs

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

**In-app purchases:** none

**What reviewers like**

- 🚀 Convenient remote control
- 👍 Customizable programs
- 🚀 Easy to use app
- 👍 Enhances sauna experience

**What reviewers complain about**

- 🐛 Unreliable app connectivity
- 🔒 Privacy concerns with data collection
- 🐛 Inconsistent scheduling and remote start
- 🐛 Buggy and glitchy app
- 👎 Limited remote functionality

**Reported bugs**

- App fails to connect to sauna
- Scheduled programs not running as expected
- Inconsistent lighting controls
- Tablet frequently restarts or loses connection

**Requested features**

- Remote start and preheat capability
- Improved app stability and reliability
- Better integration between app and sauna
- More customization options


## Frequently asked questions

### Is G21 free?

G21 is free to download, with no in-app purchases.

### Is Sunlighten free?

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

### Which has better reviews, G21 or Sunlighten?

G21 is rated higher. G21 averages 3.7 out of 5 from 3 ratings, while Sunlighten averages 2.7 from 84 ratings.

### Do G21 or Sunlighten have ads?

G21 shows ads; Sunlighten does not.

### Which is updated more often, G21 or Sunlighten?

G21 ships an update monthly, and Sunlighten every 4 months. Most recently, G21 was updated on October 15, 2026 and Sunlighten on October 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.*