# Diamond Tanning vs Underground

The clearest difference is update cadence: Diamond Tanning at monthly against Underground's every 2 months. On price, ads, in-app purchases and device support there is nothing between them.

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

Diamond Tanning ships an update monthly, Underground every 2 months. The most recent releases landed on October 24, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | Diamond Tanning | Underground |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Monthly** | Every 2 months |
| Monetization | — | Free |
| Size | 193 MB | 101 MB |
| Requires iOS | **16.0** | 16.6 |
| Devices | **iPhone, iPad** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Diamond Tanning](https://appshunter.io/developer/1781433883) | [Perfect Gym Solutions Sp. z o.o.](https://appshunter.io/developer/1004382730) |

## What reviewers say

### Diamond Tanning

[App page](https://appshunter.io/ios/app/diamond-tanning/id1210401109)

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

**In-app purchases:** none


### Underground

[App page](https://appshunter.io/ios/app/underground-gym/id1633463579)

Easily manage your fitness club experience from your mobile device. Book classes, access your membership details, and enter your club using QR codes. Stay updated with club information and class reminders.

**Highlights:** QR code club entry, Class booking, Membership management, Club information access, Friend invitations, Attendance tracking, Class reminders

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

**In-app purchases:** none


## Frequently asked questions

### Is Diamond Tanning free?

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

### Is Underground free?

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

### Do Diamond Tanning or Underground have ads?

Neither Diamond Tanning nor Underground shows ads.

### Which is updated more often, Diamond Tanning or Underground?

Diamond Tanning ships an update monthly, and Underground every 2 months. Most recently, Diamond Tanning was updated on October 24, 2026 and Underground on October 25, 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.*