From Bulbapedia, the community-driven Pokémon encyclopedia.
Rolling Voltorb (Japanese: ころがっていこう Roll Along) is the name of a Pokémon-based e-Reader application. It is a minigame featuring Voltorb. Four cards are required for the Rolling Voltorb application: Magnemite, Voltorb, Magnemite, and Voltorb.
In Rolling Voltorb, the player takes on the role of a Voltorb. In the game, Voltorb is rolling down a hill and the objective of the game is to avoid rocks and other obstacles that are in its way. The player's score increases as Voltorb rolls further down the hill. The game ends when Voltorb fails to dodge an obstacle.