Two versions were released in Japan: the original e-Reader (without a link cable port), which could read cards to unlock game content, etc.; and later the e-Reader+ (simply "e-Reader" in Australia and North America), which came with a link cable port to connect with Nintendo GameCube games such as Animal Crossing and with other Game Boy Advance systems for games such as Pokémon Ruby and Sapphire. The e-Reader was only considered successful in Japan. It was announced for Europe but very few were made, as it was almost immediately canceled, and it was discontinued in North America in early 2004, due to a lack of popularity. In Japan, it sold much better and was produced up to the discontinuation of the Game Boy hardware line.
The cards, when used with the game's post office, would provide items to players. Some were rare, while others were more Common. Some unlocked "town tunes", which were played each time the player talked to an animal, still others were "sibling" cards (series 2–4) with two related characters on the front, and yet more were tailor design cards, which unlocked new designs to be used around the village. Aside from the regular card packs, some regular series cards were distributed on a promotional basis through GameStop, EB Games, and Energizer batteries. These cards did not differ from the regular version of the cards contained within the packs sold at the Retail level.