What is OnionOS? A complete guide for Miyoo Mini Plus
OnionOS is the go-to custom firmware for the Miyoo Mini Plus. Here's what it does, how it compares to stock firmware, why most people use it, and answers to the most common questions.
If you own a Miyoo Mini Plus, you’ve probably seen OnionOS mentioned constantly in forums, Reddit, and YouTube. It’s the most popular custom firmware for the device — and for good reason. Here’s everything you need to know.
What is OnionOS?
OnionOS is a custom operating system for the Miyoo Mini and Miyoo Mini Plus. It replaces the stock firmware with something dramatically better: a polished interface, proper emulator support, RetroAchievements, Wi-Fi features, and an active development community.
The stock firmware that ships with the Miyoo Mini Plus is functional but basic — laggy menus, no artwork, limited features. OnionOS transforms the same hardware into a device that feels premium.
Key features
Interface and themes
OnionOS ships with a clean, responsive main menu and supports community-made themes. You can completely change the look of the device in minutes. The UI is fast and controller-friendly — no touchscreen required.
RetroAchievements
Connect to Wi-Fi and earn achievements in classic games, just like Xbox Achievements or PlayStation Trophies. OnionOS has built-in RetroAchievements support across all major emulators. It’s one of the most compelling reasons to use it.
Wi-Fi features
- Artwork scraping — automatically downloads box art and screenshots for your game library
- Save sync — back up save files over Wi-Fi
- Remote access — manage your SD card files from a browser on your computer
Package manager
OnionOS includes an App Store-style package manager. Install additional emulators, apps, and tools without touching a computer. Updates are handled the same way.
Sleep mode
Instant sleep and resume — press the power button to sleep, press again to continue exactly where you left off. This works across all emulators and is one of the most-used features day to day.
Emulator quality
OnionOS ships with tuned emulator configurations for each platform. The default settings are optimised for the Miyoo Mini Plus’s screen and hardware — you don’t need to configure anything to get a great experience.
OnionOS vs stock firmware vs other options
| Feature | Stock Firmware | OnionOS | GarlicOS | MinUI |
|---|---|---|---|---|
| Interface quality | Basic | Excellent | Good | Minimal |
| RetroAchievements | ❌ | ✅ | ✅ | ❌ |
| Wi-Fi features | ❌ | ✅ | ❌ | ❌ |
| Theme support | ❌ | ✅ | Limited | ❌ |
| Package manager | ❌ | ✅ | ❌ | ❌ |
| Sleep/resume | ❌ | ✅ | ✅ | ✅ |
| Update frequency | Rare | Monthly | Regular | Regular |
| Compatible devices | Miyoo only | Miyoo only | Anbernic H700 | Multi-device |
Bottom line: For Miyoo Mini Plus owners, OnionOS is the clear choice. GarlicOS and MinUI are excellent on Anbernic devices but don’t support the Miyoo Mini Plus’s hardware as well.
Is it safe to install?
Yes. OnionOS installs entirely on the microSD card — it never touches the device’s internal storage or firmware chip. To revert to stock, simply swap back to the original SD card. There is no risk of bricking your device.
The project is open source and auditable on GitHub. It has been installed on hundreds of thousands of devices without issues.
Where to download
Always download from the official OnionOS GitHub releases page. Never use third-party download sites, YouTube links, or file-sharing services — these may contain outdated or modified versions.
Check our OnionOS Firmware Tracker to see the latest version and recent changelog at a glance.
Frequently asked questions
Does OnionOS work on the original Miyoo Mini (not Plus)?
Yes — OnionOS supports both the original Miyoo Mini and the Miyoo Mini Plus. The installation process is the same. It also supports the Miyoo Flip.
Will I lose my save games if I install OnionOS?
Your saves are stored on the SD card. If you’re installing OnionOS on a fresh card, you’ll start fresh. If you’re replacing stock firmware on an existing card, back up your Saves/ folder first. OnionOS uses RetroArch-compatible save formats, so saves are portable.
How often is OnionOS updated?
OnionOS releases updates roughly every 4–8 weeks. The development team is active and responsive. Bug fixes often ship within days of being reported. See the firmware tracker for the latest release date.
Do I need Wi-Fi to use OnionOS?
No. Wi-Fi is optional. All core features — emulation, themes, sleep mode — work without a network connection. Wi-Fi unlocks RetroAchievements, artwork scraping, and save sync, but the device works perfectly offline.
What’s the difference between OnionOS and RetroArch?
RetroArch is an emulation frontend that runs inside OnionOS. OnionOS is the full operating system — it handles the menu, themes, Wi-Fi, and launches RetroArch (and other emulators) behind the scenes. You interact with OnionOS; RetroArch does the emulation work.
Ready to install? Follow our step-by-step OnionOS installation guide — it takes about 15 minutes and requires no technical knowledge.
Screen Fit Analysis
See how devices mentioned in this article handle popular platforms: