If you just want to play The Binding of Isaac portably: skip the 3DS version. Buy Rebirth + Repentance on the Nintendo Switch, Steam Deck, or even your iPhone (Netflix Games). The 3DS port is underpowered, censored, and incomplete.
While the PC and Switch versions have more expansions (like Repentance ), the 3DS version has a specific charm:
The version of The Binding of Isaac: Rebirth for the Nintendo 3DS refers to a file format (typically .3ds or .cia ) that has had its digital rights management (DRM) removed, making it playable on handheld emulators like Citra or for modding on Homebrew-enabled systems.