Onion OS or MinUI — which should I choose for the V4?

Onion OS if you want box art, themes and full RetroArch options that use the 752x560 screen; MinUI if you want a stripped-down, fast launcher. Both are free and install to the microSD.

Does the V4 need a special Onion version for its screen?

Use a current Onion release together with base firmware 202310271401 or later so the 752x560 resolution is handled correctly. Older combinations can render at the wrong resolution.

Does installing custom firmware brick the V4?

No. The V4 boots from the microSD, so CFW lives on the card. If something goes wrong you reformat the card and reinstall — the device itself is hard to brick this way.

Miyoo Mini V4 — Custom firmware

Quick answer

Steps

1Stock (Linux): the default Miyoo OS — keep it only if you want the out-of-box menu.
2Onion OS: the flagship CFW for the V4 — RetroArch front-end, themes, box art and full use of the 752x560 screen on current releases.
3MinUI: a minimalist launcher — copy MinUI.zip (do not unzip) plus the Bios/Roms/Saves folders to a FAT32 card.
4Pick one CFW per SD card and back up saves before switching firmware.

Last verified: 2026-06-20Source: onionui.github.io

The Miyoo Mini V4 runs a Linux-based stock OS, but most owners install community firmware. Onion OS is the de-facto choice on this SigmaStar device: a polished RetroArch front-end with themes and box art that takes full advantage of the V4's 752x560 screen on a current release and recent base firmware. MinUI is the leading minimalist alternative — fast, almost no menus, and shares one card across many handhelds. All firmware lives on the microSD, so you can swap between them by reflashing the card; nothing overwrites the stock system permanently. Like the original Mini, the V4 has no Wi-Fi, so Onion's online features (OTA, netplay, scraping) are not available.

FAQ

Onion OS or MinUI — which should I choose for the V4?: Onion OS if you want box art, themes and full RetroArch options that use the 752x560 screen; MinUI if you want a stripped-down, fast launcher. Both are free and install to the microSD.
Does the V4 need a special Onion version for its screen?: Use a current Onion release together with base firmware 202310271401 or later so the 752x560 resolution is handled correctly. Older combinations can render at the wrong resolution.
Does installing custom firmware brick the V4?: No. The V4 boots from the microSD, so CFW lives on the card. If something goes wrong you reformat the card and reinstall — the device itself is hard to brick this way.

Miyoo Mini V4 — Custom firmware

Steps

FAQ

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