If Gameloft's Gangstar: City of Saints on iPhone is guilty of being too straight-laced in its attempt to depict gang culture, its sister title on mobile is guilty of the opposite.

Where City of Saints felt rigid and positively lifeless on touchscreens, here the streets feel far more jumbled and hectic. Java's version of Rio is far more alive, despite the inevitable graphical sacrifices.

It's not generally fair to compare Java games with iOS games, but in this case it's worth lining the two titles up in because they're so utterly different.

Small slip ups

City of Saints on mobile avoids many of the pitfalls the iOS version fell into, but unfortunately it stumbles into some pitfalls of its own.

The plot, by and large, remains intact. Attempting to free yourself from a life of crime after almost dying in a car bomb, you vow to put your dark side behind. And then you embark on a lengthy murderous rampage.

Yes, City of Saints continues to make no sense whatsoever in narrative terms, but the streets its plays out in are at least full of life.

Split into several zones, the storyline takes you from one goal to another, marking off trigger points with blue arrows that guide you to the next mission.

Kill or be killed

As you might expect, life in Gangstar Rio: City of Saints revolves around the art of killing.

Some of those deaths will occur officially, on a mission-based basis, but many will also be the result of accidents, as you attempt to manage what prove to be awkward driving controls: '2' handles acceleration, while the keys '4' and '6' swing you left and right.

The missions themselves are up and down. Some are almost over before they've begun, with targets standing rigidly as you shoot them one by one.

Others are incredibly comical: one of City of Saint's initial missions sees you attempting to scare a passenger in a car by driving wildly – the kind of easy opener every game of this ilk throws in at some point.

To get in the driving seat in the first place, however, you first have to 'deal' with the your target's official driver before he turns up. Any sense of believability is trashed when your passenger merrily steps over the dead body of his former driver as he slips onto the back seat.

A star is yawn

More seriously, play seems to struggle when the action inevitably picks up.

When it comes to the game's police – who leap into action whenever you kill any of the city's inhabitants, with Gangstar adopting the familiar five-star rating – the AI is erratic at best.

Indeed, I suffered at the hands of couple of game-breaking bugs during play: get run over when being arrested, for instance, and the game will simply hang, requiring a restart to send you back to your last save point.

Gangstar Rio: City of Saint's Achilles's heel is that it's too ambitious.

Smart touches like regular newsflashes detailing both your exploits and the rest of the underworld help involve you in the gameworld, and the game's light tone is a welcome directional shift, but these qualities are undermined by plain and often jagged missions that do little to suggest this criminal caper is the star it claims to be.