# The Vault 164 vs Underground

The clearest difference is ads: Underground at none against The Vault 164's shown. The Vault 164's advantage is update cadence (every 3 weeks vs every 2 months) and device support (3 vs 1). On price and in-app purchases there is nothing between them.

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

The Vault 164 ships an update every 3 weeks, Underground every 2 months. The most recent releases landed on October 27, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | The Vault 164 | Underground |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | No | No |
| Ads | Yes | **No** |
| Update frequency | **Every 3 weeks** | Every 2 months |
| Monetization | — | Free |
| Size | 117 MB | 101 MB |
| Requires iOS | **14.0** | 16.6 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Qi dragon limited](https://appshunter.io/developer/1597778383) | [Perfect Gym Solutions Sp. z o.o.](https://appshunter.io/developer/1004382730) |

## What reviewers say

### The Vault 164

[App page](https://appshunter.io/ios/app/the-vault-164/id1597778381)

**Features:** macOS Compatibility, Apple Wallet

**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 The Vault 164 free?

The Vault 164 is free to download, with no in-app purchases.

### Is Underground free?

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

### Do The Vault 164 or Underground have ads?

The Vault 164 shows ads; Underground does not.

### Which is updated more often, The Vault 164 or Underground?

The Vault 164 ships an update every 3 weeks, and Underground every 2 months. Most recently, The Vault 164 was updated on October 27, 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.*