Games for the CD-i that were produced without the permission or knowledge of Philips or Sony.
The first unlicensed CD-i games appear to have been aftermarket releases of previously unreleased titles, such as the English-language version of Go, and Plunderball. As for homebrew development, the platform is not popular; since the release of Frog Feast in 2007, only a few such titles have been produced, mainly owing to the hardware's poor reliability and emulation struggles.