iPad reviews of the week: Grim Joggers, Infinity Field, Pac-Man Battle Royale, Rooms: The Main Building, Resident Evil 4

Many high-profile iOS games take a lot of flak (often well deserved) for being blatant copycats of existing properties. But although the first two games in this week's feature build upon familiar games, both Grim Joggers and Infinity Field offer truly worthwhile riffs on what we already know and love. And later in this piece, we'll look at a trio of existing titles from other platforms – Pac-Man Battle Royale, Rooms: The Main Building, and Resident Evil 4: iPad Edition – which come to the iPad with varying degrees of success.

Game: Grim Joggers
Price: $1.99/£1.19
Size: 17MB
Buy it now from the iTunes store: US/ UK

Depending on your whereabouts, a brisk jog may put you in the path of icy sidewalks, perilous potholes, or uncertain rural paths, among other potential hazards. But the ambitious joggers of this amusing universal iOS release face an entirely different sort of task: running and jumping through across arctic terrain and wart-torn battlefields, all the while avoiding killer spikes, man-eating plants, and other absurd obstacles. Can't start the day without a good sweat, though, right?

Grim Joggers takes obvious cues from Canabalt and the like, with a side-scrolling running approach that increases in speed and intensity as the seconds tick by, but makes its own mark by putting you in charge of a whopping 15 runners at the start of each stage. Tapping the screen causes your entire party to jump (or double-jump), though the daunting pits and frequent hazards that line your path will claim stragglers along the route. The goal is simply to make it as far as you can on each course until every last jogger perishes, and then repeat until you've notched lengthy runs and unlocked the later stages and various achievements.

The colorful pixel aesthetic looks a bit blurrier on the iPad than the iPhone 4, though it's an endearing playthrough on either device – and it'll even carry over your achievements between devices, which is a supremely helpful perk for those of us who love great quick-hit games like this on every available platform. And though Grim Joggers is a relatively new release, it's already been updated with an extra world (four in total, as of this writing), with another one promised within the app. With a regular stream of free content, we hope to still be talking about this one when the end of the year rolls around.

Game: Infinity Field
Price: $1.99/£1.19
Size: 17.6MB
Buy it now from the iTunes store: US/ UK

Geometry Wars Touch delivers a pretty sharp version of the classic twin-stick shooter on the iPad (and better yet, it's only a buck), but ForzeField's Infinity Field offers up the best alternative we've seen on the platform by a wide margin. The game’s “inspiration” isn't subtle – this is a full-fledged clone in the nicest sense of the term – but the new play modes and options, not to mention the near-perfect controls, make this perhaps the best shooter of its type on the iPad.

Though the Infinity mode pits your ship against the standard array of very familiar-looking enemies, it introduces new twists like letting you choose a ship that's faster or more offensive-minded, as well as letting you upgrade and swap weapons over the course of your attempt. While the other five play modes occasional touch on ideas from Geometry Wars and other such knock-offs, they feel remarkably fresh and fully formed. Consider the Zombie mode, where the shells of defeated enemies remain as on-screen obstacles until detonated with a pick-up, or Snake, where the span between your head and tail forms a laser for destroying enemies.

All six modes are great, and the game looks swell on the iPad – admittedly better than Geometry Wars Touch – but what really locks this down as a must-play are the sharp touch controls. Geometry Wars Touch gave us that not-so-responsive feeling at times, but Infinity Field performs admirably in tense scenarios, plus the game triggers an auto-pause mechanism whenever you lift your fingers – a perfect feature for the device that most other iOS games could learn a thing from.