Super Mario Bros meets Pong - there's no better way to describe the unique, unusual, and unbelievably fun gameplay of Squareball. Inspired by these classics, this unassuming title requisitions the platform play of the former and minimalist arcade style of the latter for something totally fresh.

The result is a game that dishes out a square meal of gaming goodness: nostalgic graphics, cool music, challenging gameplay, and great value.

In Squareball, you control the level, not the ball. Sliding a finger across the screen moves the stage left or right, letting you control the surfaces on which your rigid ball bounces.

The similarity to Pong is obvious, though your goal differs from Atari's seminal hit. Instead of trying to keep the ball in play for as long as possible, your objective lies in breaking special green blocks scattered throughout each level.

As in a platformer, reaching these blocks requires you to overcome an array of obstacles. Gaps in the walls and instant-kill red blocks have to be circumvented by sliding the stage left or right. Varying the speed at which you move your finger enables you to maneouvre the ball through huge gaps or precisely through tight, dangerous corridors.

Additional pressure is applied via a time limit. Parallel to a chartreuse gauge showing the number of green blocks within the level runs a salmon-coloured timer along the top edge of the screen. As you make your way through a level, the pink gauge slowly diminishes.

Thankfully, time limits never unfairly threaten your performance. In fact, you're unlikely to notice it in playing the first dozen levels. Rather than causing unnecessary anxiety, slapping levels with a time limit is a measure intended to counterbalance other elements within the game.

A time limit discourages overuse of yellow quicksand blocks that slow your ball down, which obviously make it easier to navigate through difficult passages.

Such careful, thorough balancing makes Squareball an exquisite challenge. This is a tough game, but without any frustration. There's a tinge of trial and error, but it never crosses the line into tedium. Each time you tackle a level and die, you're motivated to try again confident that you can make it past the furthest point of your last run.

The game expertly inclines the level of difficulty so that you're always equipped with the skills necessary to make it through a stage, nonetheless challenged along the way. It's unlikely that you can complete a stage in your first attempt, but when you finally nail it the sense of accomplishment is wholly satisfying.

Improvements to the checkpoint system would be welcome, though. Each level features a single checkpoint at its midpoint from which you restart if you should die. On the more difficult stages, adding an extra checkpoint or two would prevent unnecessary replay through previously completed challenges.

That Squareball matches the brilliance of its gameplay with equally superb presentation comes as no surprise. The game fully embraces its arcade roots with minimalist graphics and bit-byte musical tones. This isn't stark audio-visual design, however, as the graphics feature subtle touches such as the shifting perspective of the blocks that create a psuedo-3D look.

All of this is gravy when you consider the core reason for playing Squareball: it's pure, simple fun.