The full title is Survival Kids 2: Dasshutsu! Futago Shima, which translates to something like "Escape! Twin Islands". It's the sequel to Survival Kids, both for the Game Boy Color. Although the prequel has been released in English, Survival Kids 2 was released in Japan (in 2000) but never in another language.
You take control of one of two brothers and the premise of the game is, not suprisingly, to survive on a wild island and if you so choose, to eventually plan your escape.