The GB Operator is an adapter that allows you to play Game Boy cartridges on your PC.
Developer Epilogue (via Nintendo Life) bills the GB Operator as "a cartridge slot for your computer." The device acts via the mGBA emulator, and supports Game Boy, Game Boy Colour, and Game Boy Advance cartridges. Since it's running via your PC, however, you'll have built-in controller and cheat support, as well as the ability to update your save files no matter which platform you're playing on.
Speaking of saves, the pain of losing a corrupted file is all too real, so Epilogue says that it's "simplified the process of backing up and restoring your saves" so that you never lose a beloved Pokemon team again. You'll also be able to trigger specific limited-time events in-game, so if you missed out when the game was first available, you'll get another chance.
And if your retro development fingers are twitching, the GB Operator also offers its own tools to make classic Game Boy games. GB Studio lets you make your own titles and write them onto blank cartridges to take with you wherever you go.
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