Before its release in August 1993, many people thought that the Gameboy could not support a game as large as Zelda, but this game proved them wrong. With 8 dungeons and 12 pieces of heart, it wasn't as expansive as LttP, but that didn't take away from the playability, and it had the added bonus of being able to play it absolutely anywhere!
It was rereleased in December 1998 (a month after OoT's release) for the new Gameboy Colour. The rerelease featured a new, hidden dungeon, and a new character who would take Link's photos throughout the game. With the Gameboy Camera, you could even print them out.