There was a time when endless vertical jumpers roamed the App Store like an apex predator, devouring the spare change of those who came near them. It certainly helped that titles like Doodle Jump provided regular content updates, mixing things up and providing an ever-more-complex challenge in the process. Now it's much harder for a game in the genre to stand out, but Cordy Sky by SilverTree Media has gone for a triple-threat whammy of making their game look gorgeous; providing simple, yet unique platforming challenges; and best of all, it's free.

'Surely there has to be a catch', I hear you saying, but there really isn't. Players can download, jump in and choose from one of three control schemes (touch, tilt or swipe) and jump away immediately, collecting gears (the game's currency), power-ups that provide a small boost (or save you when you fall too low), and tokens for a post-game bonus slot machine.

Players initially find themselves trying to help Cordy (the robotic hero you control) to reach a height of 5000 meters in order to reclaim a space-ship and escape the planet. To do so you'll need to travel through five different worlds, each one introducing a handful of new challenges including bouncy orbs that vary in strength and direction; basic platforms and moving belts; rotating bumpers; and many others that are combined to provide a challenge that occasionally swings from slow and considered, to frantic and out-of-control at a moments notice.

Should you run out of boosts and fall back to the planet, the paid-for element of the game will start to rear its head as you attempt to invest your gears in to power-ups for the titular hero. Their cost can be almost stratospheric, but they're not required to complete the game and in the case of some, remove the element of challenge entirely, so you're better off sticking to the aesthetic changes.

What makes Cordy Sky so much fun is the way in which unlocked elements are incorporated in to lower-levels, making repeat runs far more interesting than the first trip up. Should you make it to 5000 meters, the game's story officially ends, but players can continue in an attempt to reach higher levels, more bonus tokens and extra gears to spend in the store.

For a free game, Cordy Sky provides more than the average endless title, while keeping things simple and gorgeous - a great pick-up for those after a cute distraction.