When asked to download a game that shares its name with a type of Mac virus unleashed back in 2006, you could be forgiven for being a tad apprehensive.

But rather than wreaking havoc on your iPhone, Leap Worm is as far from being an irritant as possible.

Leap Worm's central character may be based on a common parasite, but its cutesy exterior, simple one-touch arcade gameplay, and different difficulty modes ensure that most will be able to sample its delights – although this does come at the cost of occasional oversimplification.

Space Worm

You control a bright green space worm which must leap from one planet to another in order to reach the vortex which signals the end of each level.

At first, leaping is performed by tapping the jump button, but once you've completed the first few stages, the entire screen can be used to jump. Once you are in the vicinity of a planet, its gravitational force pulls you into its orbit.

Four difficult modes are included – Kids, Easy, Medium, and Hard – all of which feature standardised controls and basic goals.

There are two objectives to each level: to collect all the stars and to reach the vortex before the target time. A 'perfect' level is considered one in which you achieve both of these feats in a single run. Some levels are relatively straightforward, while others are more complicated and require you to visit certain planets before you can enter the vortex.

Stars in their eyes

Level elements vary according to the difficulty mode you are playing. Kids mode is naturally the easiest, as several generous concessions are made. Enemies simply repel rather than kill you, while falling to the bottom of the screen doesn’t result in instant death.

In other modes, the deceptively cute enemies are far more deadly, and the bottom of the level is replaced by a poisonous pit of gas. This means you have to be much more precise and may have to bounce off the sidewalls in order to sidestep danger.

Stars also grow in quantity and become increasingly difficult to reach. In essence, you're forced to take greater risks, and wrong moves are punished more severely.

Wormhole

Leap Worm implements its ideas effectively and the game couldn’t be more eager to help you. Even pushing the pause button results in an explanation clarifying what you’ve done.

Production wise, the bright colourful planets and backgrounds are complemented well by cute characters and enemies, while the interactive menus are a nice touch.

The simple nature of earlier levels makes the game easily accessible. That said, the arrival of more complex elements such as brittle plants and new alien enemies, coupled with longer distances between planets, necessitates taking greater risks such as blind (literal) leaps of faith.

Acing each level requires the perfect balance of speed and accuracy, even if some stages do end up just becoming a tedious, time-consuming process of acquiring an increasing number of stars.

Another gripe is the absence of a timer, which would make the pursuit of the target time far more enjoyable, particularly when attempting to perfect a level.

However, Leap Worm's charming visuals and some great level design ensure that these minor problems don’t overshadow what is a great one-touch arcade game.