It seems kind of odd, making a pinball video game. It's not unlike having one game inside another � like Lara Croft stopping off in an arcade to play a game of Pac-Man or something. That said there's no denying the strangely addictive allure of pinball video games, somehow carrying over the enjoyment of bouncing a physical ball bearing around a mechanical assault course.

The large screen of the iPhone benefits such a digital translation, as does its native portrait orientation which allows the whole table to be seen in one view � something most other platforms can't do without awkward solutions. But then most other systems have physical buttons to use as flipper controls, and it's this aspect of Zen Pinball: Rollercoaster that's the sticking point.

The corners of the screen, both upper and lower, activate the relevant flippers. Naturally the sensitivity of the touchscreen is spot on, but keeping a good grip on the actual iPhone without accidentally pressing (and often inadvertently holding down) the flippers is quite problematic. Placing the handset flat on a table seems to be the best way of handling Zen Pinball, but carrying Ikea's finest around with you is not always an option and, besides, it doesn't feel a particularly ergonomic approach even when a surface is available.

Despite the title qualifier of 'Rollercoaster', the table's theme seems to be more of a carnival, or funfair. It's a great premise for a pinball table as it allows for lots of twists, turns, rails and holes to send the ball rocketing around. While the sound effects match this carnival concept very nicely, the music is a little lacklustre and generic. Thankfully, you're able to listen to your own tunes by setting your iPod on play before jumping into the game.

The viewpoint takes advantage of the iPhone's motion sensing capabilities in quite an interesting way. The 'camera' can either be locked in the expected first-person position, or the handset itself takes on the physical presence of the table. So lifting and rotating the iPhone is like moving around the table, which is an interesting device, but doesn't actually make a whole lot of difference to the gameplay. Should you adopt the method of laying the handset flat to play the game, it also makes the visuals a little two-dimensional, since you're essentially given a bird's-eye view of the pinball machine.

All niggles aside, Zen Pinball: Rollercoaster is an accurate and enjoyable digitisation of a pinball table that's the equal of those to come before it. The majority of the problems are systemic faults in the general concept of a digital pinball game, but Publisher X isn't asking a lot for it, so if you harbour any intrigue for such a game you'll not be disappointed.