APP OF THE WEEK:9 cert, Chillingo/Games Faction, iPad (also iPod Touch, iPhone)

It’s appropriate to have an app game set on a train: commuter vehicles and apps are frequent bedfellows, after all. Storm the Train is a simple, endearing and compulsive side-scrolling shooter. Control a choice of three characters as they storm the locomotive, mainly running from left to right and shooting an army of monsters along the way.

The controls are simple but the game is challenging, as the hordes of enemies and their bosses start to take their toll. Just as the undead in Plants vs Zombies are more appealing than sinister, Storm the Train belies its B-movie horror premise with cute, funny graphics and amusing details. For example, the music changes from old-fashioned eerie horror score (for zombies and vampires) to retro synthesizers when you board the killer robot train. You can buy power-ups and enhancements via micro-transactions. This diverting, knowing and engaging app game is worth the cover charge.