Released on the 17th of September 2002 in North America, the Nintendo e-Reader was a Game Boy Advance add-on with a slot that can read specially coded cards. The e-Reader incorporates a laser scanner that reads "e-Cards" which use Olympus Optical Co., Ltd.’s special barcode technology.

When the e-Cards are scanned, the e-Reader translates the code into data that the Game Boy Advance turns into multimedia content or game data such as mini-games, game information, game updates and a large variety of other things that could be unlocked, enhancing the portable experience and giving a boost to the longevity of the Game Boy Advance.

e-Cards are basically standard trading cards but with one or two strips of dots on the edges to swipe: the device requires a somewhat slow, fluid and firm swipe, not a quick flick. Maybe the best way is to leave the Game Boy Advance on the desk and just slide the e-Card through horizontally. The user only needs a couple of try-outs to understand the correct swipe speed. If something goes wrong with the scan operation, the console will report a "Read Error" message. Also many e-Card applications are segmented into multiple cards, and the user must therefore scan all the cards to load the complete application into the Game Boy Advance.

With the North American device are packaged two foil packs of cards: a NES-e title (either Pinball-e or Donkey Kong Jr.-e, the included card is marked on the package) and the "Sample Pack 5 Card Set", which includes Manhole-e, Animal Crossing promotional cards and three Pokémon Expedition cards (Machoke, Machop, and Machamp).

The e-Reader hardware sold in Australia is the exact same as the one sold in North America (so all US e-Cards work on the Australian e-Reader and vice versa), but there are packaging differences:
- In Australia, the e-Reader is sold in a small cardboard box, not the large clamshell packaging that is used in North America.
- There is a small piece of plastic included in the box, which is designed to protect the screen when the e-Reader is used with a Game Boy Advance SP.
- The promotional e-Cards packed with the Australian e-Reader are different from those in the US: four exclusive Pokémon Battle-e cards, Hockey Card-e, Manhole-e (same e-Card as in the US), and Donkey Kong Jr.-e.

There are two models of the e-Reader in Japan. The "old" Japanese model (called the "Card-e") has only half the internal memory compared to the US model, it doesn’t have a Flash ROM (so it cannot store games like the US model can) and it doesn’t have a Link Cable port. The US model has the Link Cable port, a built-in NES emulator that allows classic NES games to be played on the Game Boy Advance, and there’s also a female voice that gives instructions in English while you are using the e-Reader. Since July 2003, a newer e-Reader model is available in Japan (called the "Card-e+") which is essentially the Japanese version of the US model, with all the bells and whistles that are in the North American and Australian models.

The encoding on the US e-Cards is different from the one used for Japanese e-Cards. Scanning a Japanese e-Card with a US e-Reader will not work. Scanning a US e-Card in a Japanese e-Reader will not work either.

The installation of the device is very easy, it’s just simply plug & play; a user only needs to pop the unit into the cartridge slot, then slide the e-Reader peripheral into the Game Boy Advance cartridge slot and if it’s properly inserted, the little connector on the front should fit into the hole in the top of the Game Boy Advance. To link it to the GameCube, plug one side of the GBA-to-GC Link Cable on the very top of the e-Reader, and plug the other end into the controller 2 slot of the GC.
When the user powers on the device, he can choose between either A) to swipe a card, B) put the unit in communication mode so that it can interface with a GameCube or another Game Boy Advance, or C) load an already installed program from the e-Reader’s flash memory.

A couple of undocumented functions are in the device, these are commonly known as "Easter eggs".
- Press the "Select" button at the title screen to see the credits roll.
- Hold L and R while turning on the Game Boy Advance with the e-Reader in it. You will be prompted with a message that asks you if you want to erase the data in memory.

The e-Reader works with the Game Boy Advance and the Game Boy Advance SP, but it is not supported by the Nintendo DS or the Game Boy Micro. Since the American and Japanese Game Boy Advance are identical, you can use a Japanese e-Reader with a US Game Boy Advance.