The Hyperkin RetroN Sq is a cube-shaped home console that accepts physical Game Boy, Game Boy Color, and Game Boy Advance cartridges and outputs them to a modern TV at 720p via HDMI. It achieves this by using software emulation: when you insert a cartridge, the system dumps the game data onto an included 512MB microSD card, then runs the ROM through an open-source emulator rather than reading the cart directly during play.
That distinction matters more than it might seem. The RetroN Sq is not a cycle-accurate hardware clone. It is a small Linux-based device running modified open-source emulation software, which is why Game Boy and Game Boy Color titles are listed as fully supported while Game Boy Advance compatibility is officially designated as a beta feature. Understanding those layers explains both what the console does well and where it runs into friction.
How does the RetroN Sq actually output 720p over HDMI?
The console upscales all output to 720p at 60 frames per second through its HDMI port, and a physical switch on the back lets you toggle between a 4:3 ratio (which keeps the original Game Boy’s boxy proportions) and 16:9 (which stretches the image to fill a widescreen panel). Neither ratio is a perfect match for the actual screen dimensions of the original hardware, so some cropping or stretching is unavoidable regardless of which mode you choose.
The box in the carton is small: roughly 3.5 inches tall, about the footprint of three Game Boy Advance units stacked side by side. It ships with a 3-foot HDMI cable, a 6-foot USB-C power cable, an AC adapter, and a wired USB “Scout” controller with a 10-foot cable. The Scout’s layout is modeled after the SNES pad, which suits the Game Boy library well given that most titles were designed for a two-button face layout.
What emulator runs under the hood, and why does it matter?
The RetroN Sq runs modified open-source software licensed under GPL terms. For Game Boy Advance titles, the system uses emulation that the community has identified as mGBA-based, one of the most accurate GBA emulators available. For Game Boy and Game Boy Color cartridges, the system relies on a separate open-source emulation layer.
Here is where the ROM-dump process becomes relevant. When you insert a cartridge, the console copies its data to the microSD card before anything plays. Original Game Boy games tend to load in three to four seconds. Game Boy Color titles take a bit longer. GBA games, being larger files, can take considerably more time to dump, and some titles have required owners to remove and reinsert the cart before the system recognizes it correctly. The upside of this approach: once a game is dumped, the cartridge functions as a license key. The downside: the console will not work with multi-game flash carts or EverDrive-style devices.
What Game Boy Advance games actually work?
Game Boy and Game Boy Color cartridges run reliably on the RetroN Sq for the vast majority of official releases. GBA support is a different situation. Hyperkin’s own firmware page notes that “some titles may work, but not at 100% capacity.” Early firmware versions made GBA performance genuinely rough, with frame rate issues severe enough to affect timing-dependent games. Subsequent updates improved stability, and the system ships with firmware pre-installed rather than requiring buyers to update immediately.
The games most likely to cause trouble are those with unusual cartridge hardware. Titles like WarioWare: Twisted! and Kirby Tilt ‘n’ Tumble rely on gyroscope sensors built into the cartridge itself, and no TV-connected console can replicate that. Reproduction carts and ROM hacks also tend to behave less predictably than original releases. If your collection is primarily authentic retail cartridges, your compatibility rate will be noticeably higher than if you are working with third-party reproductions.
What should you know about save files before you start playing?
This is the one area that surprises most buyers. All in-game saves are written to the microSD card, not back to the cartridge. Saving progress in Pokémon FireRed on the RetroN Sq will not update the save file on the physical cartridge itself. If you later take that cart to a friend’s Game Boy Advance SP, you will load from whatever save was on the cartridge before you started playing on the Sq.
Firmware updates also erase all saves stored on the microSD. Hyperkin’s firmware page states this plainly: updating will delete game progress stored on the console, while save data on the cartridge remains untouched. The practical advice is to finish a game or reach a natural stopping point before applying any firmware update, and to treat the RetroN Sq save files as separate from your cartridge saves rather than as extensions of them.
The RetroN Sq Is the Straightforward Answer for Big-Screen Game Boy Play
If you own a box of Game Boy, Game Boy Color, and Game Boy Advance cartridges and want to see them on a living-room screen without building a MiSTer setup or hunting down a GameCube Game Boy Player, the RetroN Sq is the most direct path. Plug it in, insert a cart, and the game appears at 720p on whatever TV is nearby. Game Boy and GBC titles work cleanly for most official releases. GBA support is real but imperfect, and buyers who go in knowing that will not feel misled.
Hyperkin has been building retro-focused consoles for years, and the broader RetroN line reflects that experience. If you want to explore what else that catalog covers, the Hyperkin RetroN 5 Console handles GBA cartridges alongside NES, SNES, Genesis, and more in a single unit, and may suit collectors whose libraries span multiple platforms.
Frequently Asked Questions
Does the Hyperkin RetroN Sq require a cartridge every time you play, or can it store games on the microSD?
The cartridge must be physically inserted each session. The console dumps the ROM to the microSD on boot and uses the cartridge as a form of authentication, so removing it stops the game. The system cannot play games stored directly on the microSD without the corresponding cartridge present.
Will the RetroN Sq work with Japanese or PAL Game Boy cartridges?
Yes. The RetroN Sq is region-free because the original Game Boy, Game Boy Color, and Game Boy Advance hardware had no region lockout. Japanese cartridges fit the same slot and will load through the same emulation process as US releases, though compatibility with any specific title still depends on the current firmware version.
Can I use a controller other than the included Scout with the RetroN Sq?
The console accepts USB-A controllers, so any USB-compatible gamepad can be plugged in directly. The RetroN Sq also supports Hyperkin’s Bluetooth controllers, including the Cadet and Admiral models, when paired through the AlphaStar BT adapter accessory.
Does the RetroN Sq support Game Boy Advance SP cartridges, or only standard GBA carts?
The GBA cartridge slot on the RetroN Sq accepts standard Game Boy Advance cartridges, which are the same format used by the Game Boy Advance SP. Both systems use identical cart dimensions, so SP-era titles like Castlevania: Aria of Sorrow or Mother 3 (Japanese release) load through the same beta-supported GBA pathway.
What happens to my cartridge’s original save file when I play on the RetroN Sq?
The console reads the existing save from the cartridge when you first boot a game and copies it to the microSD. From that point forward, all new saves write to the microSD only, leaving the cartridge’s original save file unchanged. If you switch back to playing on a physical Game Boy, your progress from the RetroN Sq will not be reflected on the cart.