# must be one vs Illusion Corridor

The clearest difference is in-app purchases: must be one at none against Illusion Corridor's 1. Illusion Corridor's advantage is ads (none vs shown) and update cadence (every 2 days vs every 5 weeks). On price, device support and iOS requirement there is nothing between them.

Both are free to download. Illusion Corridor sells 1 one-off in-app purchase. must be one asks for nothing beyond the download.

must be one ships an update every 5 weeks, Illusion Corridor every 2 days. Both last shipped on October 31, 2026.

## The numbers

| Metric | must be one | Illusion Corridor |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (1 ratings)](https://appshunter.io/ios/app/illusion-corridor/id6800756593/reviews)** |
| Number of ratings | — | **1** |
| In-app purchases | **No** | Yes |
| Ads | Yes | **No** |
| Update frequency | Every 5 weeks | **Every 2 days** |
| Monetization | — | Free with in-app purchases |
| Size | 6 MB | 3 MB |
| Requires iOS | **15.6** | 16.0 |
| Devices | **iPhone, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [office-canard games](https://appshunter.io/developer/6793797221) | [Qingyu Chen](https://appshunter.io/developer/1629701754) |

## What reviewers say

### must be one

[App page](https://appshunter.io/ios/app/must-be-one/id6794124997)

**In-app purchases:** none


### Illusion Corridor

[App page](https://appshunter.io/ios/app/illusion-corridor/id6800756593)

This isometric puzzle game challenges players to manipulate perspective and mechanisms to create impossible paths. Explore seven chapters with 65 handcrafted levels, featuring rotating bridges, sliding platforms, and more. Enjoy a quiet, offline experience with no ads or in-app purchases after the initial unlock.

**Highlights:** Isometric perspective puzzles, Manipulate mechanisms and platforms, 65 handcrafted levels, Offline play, No ads or subscriptions, Multiple languages supported

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Full Game | $2.99 | one-time |


## Frequently asked questions

### Is must be one free?

must be one is free to download, with no in-app purchases.

### Is Illusion Corridor free?

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

### Do must be one or Illusion Corridor have ads?

must be one shows ads; Illusion Corridor does not.

### Which is updated more often, must be one or Illusion Corridor?

must be one ships an update every 5 weeks, and Illusion Corridor every 2 days. Most recently, must be one was updated on October 31, 2026 and Illusion Corridor on October 31, 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.*