...is a Poké Ball-shaped pedometer which can connect to Pokémon SoulSilver and HeartGold game cards via infrared signals. The player can transfer a Pokémon to the Pokéwalker from either SoulSilver or HeartGold. Every time the player takes a step, the Pokémon inside gains experience points and the player earns 'Watts', a type of in-game currency which was also used on the Pokémon Pikachu virtual pet. Players can also catch various Pokémon on the device and obtain items, then transfer them to the game. The device comes bundled with the games.
When players transfer a Pokémon from their game into their Pokéwalker, they can select which route they would like to take their Pokémon along. Depending on which route the player takes (such as in a grassland or by the sea), they will encounter different wild Pokémon and items. When players first begin their journeys with the Pokéwalker, the list of routes they can select from is short. But, the more players take a stroll with their Pokémon, the more routes will appear and the more Pokémon and items they will be able to get.
One criticism of the pokewalker is the ease of 'cheating' or 'hacking' in which players will intentionally create artificial situations mimicking walking. This has consequently led to multiple varieties of Pokéwalker cheats causing Pokémon to gain experience without the user actually expending any effort. Nevertheless, the device has still been praised as a good way to get kids active and to have fun at the same time.
What's it worth? Take a look at this Nintendo Pokewalker price guide: sold listings for a value indication.