The tower defence genre is a favourite for mobile platforms, a formula – build heavily armed obstacles to halt a determined offensive force – that the Anomaly series twisted to great success, by putting players in charge of the attackers instead. Anomaly 2 (Chillingo, iOS, £2.99) furthers the concept, allowing you to guide a force of tanks through a winding road guarded by enemy towers.

It looks amazing – in fact the sheer graphical heft makes it a heavy burden for older iPhone models – and the gameplay has been changed, with the ability to transform tanks on the fly and drop power-ups along the course as you plot the best way to stay the course. The multiplayer mode is also a fine addition, one player guiding tanks, the other placing towers – an intelligent add-on to the experience.

Anomaly 2 is an impressive-looking, surprisingly tactical challenge that cements the series at the pinnacle of the genre.