Welcome to the weekly iPhone Quality Index (Qi) games round-up, 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 (such as 148Apps, Macworld, and Slide to Play) to establish a single definitive Qi score for each iPhone app and game.

Wheelie great

Elephant gliding and boomeranging onto Qi’s playground as the top dog this week comes Touchgrind BMX, Illusion Labs’s spiritual successor to skateboarding simulation Touchgrind.

A trio of spectacular assessments from around the iPhone universe have propelled this on-rails trickster to a high-flying 9.4 Qi rating, leaving all of its wheelie-popping rivals trailing in its wake.
AppSpy contends that you’ll be performing insane bike stunts almost immediately, for, "getting used to the two-finger control system doesn’t take a lot of time as the top finger steers the bike while the rear provides power, making it a snap to get around."

Rings of Glory

Prequels in the movie business make a disturbing habit of ruining a franchise’s reputation (yes, Star Wars: Episode 1 - The Phantom Menace and Hannibal Rising, we’re thinking of you).

Fortunately for Japanese publisher Square Enix, iPhone games that prefigure a later work don’t follow the same torturous rulebook, as the refined, exploratory, and engaging RPG Chaos Rings Omega ably demonstrates.

In a story set 10,000 years before the events of Chaos Rings - one of Qi’s top ten picks of 2010 - you reprise the role of the (quite considerably more) youthful Veig and compete in a series of life-or-death skirmishes at the Arc Arena tournament.

Defence as the best form of attack

After it famously obtained the trademark for the term ‘tower defense’ in June 2008, Com2uS is now on a mission to produce the definitive entry in this popular genre.

With its 40 campaign maps, nine unique strongholds, and five alien landscapes, Tower Defense: Lost Earth may well have delivered on the Korean game maker’s promise.

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