In the meantime a torrent of nervous-looking new arrivals joined the App Store, so it’s time for me to line a few of them up and judge which are fit for action and which should be sent home on indefinite leave.

This week I’m looking at Wallpapers by Gelaskins, Star Trigon Lite and EuroTalk.

Wallpapers by Gelaskins (free) – Where does one find a raft of beautiful wallpapers, all designed by internationally acclaimed artists and proportioned perfectly for the iPhone? Step up Wallpapers by Gelaskins, packed to the very brim with seriously high-quality papers. The selection of artists on offer is nothing short of jaw-droppingly impressive, including, I’m pleased to note, Alien-artist H.R. Giger. The app is free and if you’re iPhone is in need of a makeover this should be your first stop.

Star Trigon Lite (free) – Japanese game shop Namco – you’ll know them from classics such as Soul Calibur, Tekken and Pac-Man – have brought their game-design skills over to the iPhone with Star Trigon. It’s simple one-click play: as the cutesy spaceman circles planets, tapping the screen catapults him round the galaxy catching Uchujin in the process. No, I don’t quite understand either, but the full game costs a few bucks and this free demo is quite strange but great fun.

EuroTalk (free) – Simple ideas, executed with flair and polish, can often be the most effective, especially on the iPhone. Created by EuroTalk, a company specializing in language learning, this app teaches you how to say hello in one hundred and fifteen different languages. For such a simple concept, it’s ultra-polished with an integrated map, search functionality and even a cute little greetings mini-game.

It seems that we’re all out of time for another week’s App Store perusing. But, as always, I’ve managed to spare a moment to tell you all about some interesting iPhone-related goings-on. Purchasing buggy apps from the App Store will never cease to be frustrating, so it’s gratifying to see that this week, one developer is doing something about it (either that or they got their wrists slapped by Apple).

Released a couple of week’s back, Gameloft’s Guitar Rock Tour was an ultra-polished pretender to Tap Tap Revenge’s iPhone rhythm-action throne. The game featured multiple instruments, a selection of (none too shabby) sound-alike hits – including Message in a Bottle and Rock You Like A Hurricane – and even a story-based tour mode complete with wacky awards.

Unfortunately, the game featured a show-stopping bug that meant songs became almost impossible to play as they disappointingly drifted out of time. As the reviews rolled in, most noting this awful bug, Gameloft kept schtum and didn’t comment. Despite the fact that they’ve released some pretty poor titles on the iPhone already, this was quite a let-down for such a large and well-respected publisher.

At some point over the past week, Guitar Rock Tour disappeared without a trace, leaving purchasers of the bug-ridden Rockband-wannabe somewhat in the lurch. Did Apple pull it from the store amidst a kerfuffle of complaints, or did Gameloft make an executive decision to reign the title back in and polish over that awful bug?

Before we could finish pondering this thought, the game returned to the store with the promise of, “Increased stability.” It seems Gameloft heard the masses and made some changes. And yet surely, with a little bit of testing and some more time in development, Gameloft could have avoided this whole mess. Never mind though, it’s the weekend, time to kick-back, chill and grab some new apps.

I’ll be back next Saturday with more apps and more recommendations, in the meantime, drop by the comments and let me know what apps you’ve tried this week (and your thoughts on the Guitar Rock Tour situation too).

Related research and analysis from GigaOM Pro:
Subscriber content. Sign up for a free trial.

• How to Market Your iPhone App: A Developer’s Guide
• Virtual Worlds: Trends and Opportunities

Guitar Rock Tour has arrived to challenge Tap Tap Revenge‘s rhythm-action throne. The new arrival touts a bevy of terrific tunes to tap along to, plus the option to play drums or guitar, loads of characters and unlockable awards.

While Guitar Rock Tour may be Rock Band squished on to the iPhone, it’s just as loud and rocks just as hard. Whereas Tap Tap Revenge is free, Guitar Rock Tour costs a few bucks ($9.99) and as such is polished better than a factory fresh Fender Strat.

At the core of any decent music-based game is the soundtrack and, while all of the song in GRT are sound-a-likes of the real thing, these are well performed covers and during a frenetic, in-game jam session the tracks come across as hard-rocking and suitably authentic.

Choose your track in Guitar Rock Tour

There’s a real range of tunes too, most of them classics in their own right, from contemporary tunes like Bloc Party’s Banquet across to classic hits with recognizable riffs such as Message in a Bottlee by The Police. Conversely, Tap Tap Revenge is heavy on excellent, yet obscure, indie and electronic artists spiced with a few chart-topping acts like Kaiser Chiefs and The Offspring.

In essence, the soundtrack for Tap Tap Revenge is more experimental and certainly more edgy. Where Gameloft call on a Blink-182 cover for some cool caché in Guitar Rock Tour, the folks at Tapulous feature girl-kissing chart topper Katy Perry’s latest hit in Tap Tap Revenge.

Play drums too in Guitar Rock Tour

One thing that Guitar Rock Tour implements wonderfully is multiple instruments. For each track you’re able to choose between shredding your way to fame on guitar or beating your way out of obscurity on the drums. In particular, playing the guitar is a joy: with chords executed in a smart way and techniques included for hammer-ons and pull-offs.  As a result, it’s far more tactile-feeling than TTR.

Another feature in Guitar Rock Tour that is absent from Tap Tap Revenge (though not necessarily missed), is a Tour mode. After picking a character and signing a cartoony contract, you and your amateur band take to the road, playing tunes across the U.S. and Canada, and rocking your way to stardom.

Along the way you also pick up various awards, meet some odd characters and unlock new tracks to play live. The story is indeed silly, yet it’s great fun and certainly a compelling way of playing through the game’s selection of 17 tunes.

Stylized clarity in Tap Tap Revenge

In terms of the graphics, the aesthetic in Tap Tap Revenge has a stylized clarity, suiting tons of musical genres, while Guitar Rock Tour is designed with a gritty rock feel — it’s like Guitar Hero meets one of those dingy little bars where the bands jam around Hendrix tunes. Effectively, it’s cliché but it works and screams of console-gaming.

But although Guitar Rock Tour clearly means business, there’s a show-stopping bug that lets the entire game down. On tracks that require more shredding and finger-picking, the backing track falls out of sync with the guitar track. As a result, the game suddenly becomes a lot harder to play and the music ends up sounding like a bad covers band who can’t seem to play in time.

The folks over at Gameloft have made a raucous rocker of a music game, with a stomping soundtrack too, and yet sometimes it just doesn’t work. For now, we’d say hold back from investing until Gameloft patches the problem and releases an updated version of Guitar Rock Tour.

In the mean time, grab Tap Tap Revenge, it may not have all the extras of Guitar Rock Tour, but it’s free, plays very well and includes some fantastic tunes too.

Related research and analysis from GigaOM Pro:
Subscriber content. Sign up for a free trial.

• Why iPad 2 Will Lead Consumers Into the Post-PC Era
• The Near-Term Evolution of Social Commerce
• Content Farms: The Players, The Benefits, The Risks