Welcome to the weekly iPhone Quality Index (Qi) games roundup, giving you the LOWdown on the HIGH scorers every Friday on these illustrious pages.

As you may already know, Qi trawls the web for iPhone game reviews from the world’s most respected online and print sources.
Qi then applies its own magic formula to each site (including 148Apps, Macworld, and AppSpy) to establish a single definitive Qi score for each iPhone app and game.

Perfect racing line

Accelerating at a rate of knots onto the App Store and up the Qi rankings with a 9.5 rating comes DrawRace 2, the hugely anticipated line-drawing sequel published by Chillingo and developed by the original’s pit crew RedLynx.

In almost every conceivable way the maker has upped the ante in this follow-up to the ingeniously devised DrawRace: the top-down visuals have been tuned up and polished, an online Friend Challenge mode has been introduced, and a new Turbo Button has enhanced the strategic element.

The velocity with which you draw your finger over the iPhone’s touchscreen determines the speed of your motor on the track, so tracing out a path through tight corners and twisty chicanes becomes an exercise in restraint.

Without question, DrawRace 2 is the natural heir to Flight Control’s iOS line-drawing crown, a view echoed by TouchGen’s lead driver: “With a hefty career mode, Crystal and Game Center integration, local multiplayer that is at the top of its class, online World League to climb and excellent visuals, it is hands down the best game out there.”

Quarterback sneak

With the New Orlean Saints and the Green Bay Packers kicking off the 2011 edition of the NFL regular season on September 8th, American-football fever is well and truly in the air.

Hence, NaturalMotion has just unleashed the latest in its series of gloriously visceral gridiron games, NFL Rivals, which follows in the decorated cleats steps of Backbreaker Football and Backbreaker 2: Vengeance.

Run the officially licensed pigskin gauntlet all the way to the end zone, spinning, juking, trucking, and sprinting past waves of oncoming linebackers en route to another touchdown and the inevitable OTT celebration routine.

Jaw-dropping animations captured by the publisher’s in-house motion picture tech and a unique levelling-up system provided a compelling case for a trio of iPhone reviewers, including Gamezebo:

“In addition to adhering to the (NFL) schedule, everything you do in the game will earn your team ‘NFL points’. These get added to an overall pool that everyone playing NFL Rivals contributes to, so you can see which team has the most active/accomplished iOS gamers for fans.”

You can get the up-to-date information about which games are reviewing best over at the Quality Index.