The Hyperkin SmartBoy is a physical controller shell that clips onto an Android USB-C smartphone and reads original Game Boy and Game Boy Color cartridges, letting you play them on your phone’s screen with real tactile buttons. It does not stream or emulate on its own: it dumps the ROM data from the cartridge into your phone’s memory, then hands off to a third-party emulator app of your choice. That process works, but it comes with a real set of conditions worth knowing before you buy.
The SmartBoy started life as an April Fools’ joke in 2015 and became a shipping product two years later. In 2026 it remains one of the only accessories that gives you a legal path to playing your physical Game Boy library on modern hardware, which is exactly why collectors and retro enthusiasts keep asking about it.
How does the Hyperkin SmartBoy physically work?
The SmartBoy is essentially the bottom half of a classic Game Boy, minus the screen. It is a controller shell that snaps onto the bottom of an Android phone via a USB-C connection. The shell weighs roughly 90 g without a phone inserted, and the D-pad has about 1 mm of travel with a satisfying click that is closer to a modern Nintendo handheld than to the mushy original DMG pad. The A and B buttons are domed and sit at a slight angle, matching the original layout. A cartridge slot on the back accepts standard Game Boy and Game Boy Color carts. When you insert a cartridge and launch the companion app, the SmartBoy reads the ROM off the physical cart and loads it into your emulator.
That last part matters: the SmartBoy does not include its own emulator. You need a compatible third-party app installed on your phone. The companion app (available on the Google Play Store) handles the cartridge communication and passes the ROM to whatever emulator you have configured. Setup takes about five minutes once you know what you are doing, but first-timers will probably spend longer sorting out app permissions and emulator compatibility.
Which Android phones are compatible with the SmartBoy?
Compatibility is the SmartBoy’s biggest practical constraint. The device requires a USB-C Android phone and will not work with iPhones, older micro-USB devices, or any phone where the USB-C port sits on the side rather than the bottom center. The shell is designed around a specific port-and-grip geometry, so phones wider than roughly 80 mm or with a camera bump that conflicts with the grip rails may not seat correctly.
In practice, most mid-size Android phones from major manufacturers released between 2019 and 2026 fit without issue. Very tall phones (above 165 mm) tend to feel top-heavy in the grip, and foldables are a non-starter. If you have a compact or standard-size phone with a centered USB-C port, you are probably fine. If you have a large or ultra-wide device, check community fit reports before buying.
What games can you actually play, and how do they look?
The SmartBoy reads original Game Boy (DMG) and Game Boy Color cartridges. Game Boy Advance cartridges are a different physical format and do not fit the slot. Battery-backed save files on the cart are preserved, so your Pokémon Gold progress stays intact between sessions, which is a detail that matters to anyone with a long-running save.
Display quality depends almost entirely on your phone’s screen and your emulator’s upscaling settings. A 1080p AMOLED panel with a good integer-scale filter produces a sharp, clean image that the original hardware could never match. Color accuracy on GBC titles is generally good, though some emulators apply color correction by default that shifts palettes away from the original LCD look. That is a toggle in settings, not a hardware limitation.
Audio is routed through your phone’s speaker or headphone output. Latency is low enough that it does not interfere with gameplay in most titles, though rhythm-heavy games can expose the occasional frame of audio lag depending on your device and emulator buffer settings.
Is the SmartBoy worth buying in 2026?
For someone with a physical Game Boy or Game Boy Color cart collection, the SmartBoy fills a gap that no other single product covers at this price point. Dedicated retro handhelds like the Hyperkin RetroN 5 play Game Boy carts on a TV with HDMI output, which is a different use case. The SmartBoy is specifically for portable play using hardware you already own.
The friction points are real: you need a compatible phone, a working emulator app, and some patience during first-time setup. The shell also adds meaningful bulk to your phone, so this is not something most people will carry daily. But for a retro gaming session at home or on a long trip, it does exactly what it promises.
Hyperkin has been building retro-compatible hardware for years, and the SmartBoy reflects that experience. The cartridge reader is reliable, the buttons feel considered rather than cheap, and the build quality holds up to regular use.
The SmartBoy Is the Right Tool for a Specific Problem
If you own physical Game Boy cartridges and want to play them on a modern screen without buying a dedicated console, the SmartBoy is the most direct solution available. It will not suit everyone: phone compatibility limits the audience, and the emulator setup adds a step that pure plug-and-play buyers will find annoying. But for collectors who already have the carts and a compatible Android phone, it is a focused, well-built accessory that does its job without unnecessary complexity.
If you find yourself wanting a dedicated retro console experience on your TV instead, the Hyperkin RetroN 5 plays Game Boy, Game Boy Color, and Game Boy Advance cartridges via HDMI and is worth considering alongside the SmartBoy depending on where you do most of your gaming.
Frequently Asked Questions
Does the Hyperkin SmartBoy work with Game Boy Advance cartridges?
No. The SmartBoy’s cartridge slot accepts original Game Boy (DMG) and Game Boy Color carts only. Game Boy Advance cartridges use a shorter, wider connector and will not fit the slot. If GBA support is your priority, a dedicated multi-cart console is a better option than the SmartBoy.
Do you need to own the original cartridge to use the SmartBoy, or can you use a ROM file?
You need the physical cartridge inserted for the SmartBoy to function. The device reads ROM data directly from the cart through the USB-C connection. It cannot load ROM files from your phone’s storage on its own. The companion app passes the dumped ROM to your emulator, but the cart must be present in the slot.
Will the SmartBoy fit a Samsung Galaxy S24 or similar flagship phone?
Most standard-size flagship Android phones with a bottom-centered USB-C port fit the SmartBoy without issue. The Galaxy S24 (not the Ultra) seats correctly for most users. The S24 Ultra’s width and camera placement can cause fitment problems. Always check the current phone dimensions against the SmartBoy’s listed grip width before purchasing.
Does the SmartBoy drain your phone battery faster than normal?
Yes, noticeably. The SmartBoy draws power through the USB-C connection and the emulator keeps the processor active, so battery consumption is higher than typical phone use. Most users report losing 20 to 30 percent battery per hour depending on screen brightness and device. Gaming with a battery pack attached is a practical workaround for longer sessions.
Can you save your game progress when using the SmartBoy?
Battery-backed save data on the original cartridge is preserved between sessions, so games like Pokémon that save to the cart work as expected. Emulator save states, if your app supports them, are stored on your phone and are separate from the cart’s battery save. Both methods work, but cart saves depend on the cart’s internal battery still being functional.