A one-button jump and run game, G-Switch takes the formula that made Canabalt so successful and adds an eponymous gravity-switching mechanic to create a twitchy, fast-paced experience with surprisingly zen-like results. It's a flawed masterpiece of a game, which is a shame because when it shines it really shines. More than just a clever combination of two well-tread game ideas, G-Switch is a reinvention.