Mobile applications aren't just for smartphone-waving wannabe business gurus – they can just as easily be for fun, flirting and football as well as watching share prices slide.

A lucrative new business opportunity for networks and developers alike, the surge in demand for downloadable mobile applications means one thing: whoever has the best store stands to gain the vote of the new generation of app fans.

So with stalwarts Nokia and BlackBerry up against the might of mobile upstarts like Google and Apple, we thought we'd do a bit of window-shopping to find out what's in store…

Apple App Store

Steve Jobs' initial refusal to give any ground to networks with the iPhone has left the App Store with a seemingly unassailable lead in the market. With no network involvement and only a single handset to cater for, third-party apps can flourish – and do.

Unlike the stores of Nokia and BlackBerry, both the iPhone and the App Store have been built from the ground up as totally new concepts. The result? An interface that engenders a feeling of being 'at one' – simple, intuitive and unmistakably Apple.

The App Store is burgeoning with thousands of applications covering every possible use, from Tube updates to 'Pull My Finger' (we'll let you guess what that one does…). Browsing is a joy, and each app comes with a comprehensive description and numerous user ratings and comments to help decision-making. There's also usually a screengrab of each app to give you a better idea about how it works before downloading. Complaints tend to centre around apps causing crashes and updates wiping data, but you run that particular gauntlet with most third-party apps.

Shortcuts to Featured Apps, Categories, Top 25, Search and Updates are located in a bar at the bottom of the screen – the latter letting you know as soon as a new version of an installed app becomes available. Categories are too extensive to list here (there's 20), suffice to say they're comprehensive. The Search function is therefore invaluable, acting like the Spotlight feature on OS X Macs.

Before the App Store, few people knew it was even possible to get applications for their phone outside those supplied with the handset. Now it's one of the main drivers in the market. Some feat for a mobile newbie.

Google Android Market

The Android Market had just over 50 apps on launch – considerably smaller than the 500-plus Apple had ready to tempt punters at the outset of its App Store. But with the free-loving world of the open-source community and the lack of restrictions placed on developers, it won't be long before the shelves of the Android Market are overflowing with innovative apps.

Like all things Google-related the Android Market is clean and simple to navigate, right from the moment you tap that shopping-bag icon. The main menu consists of a bar with featured apps, followed by a list of the main categories underneath: Applications, Games, Search and My Downloads. Each category has a range of sub-categories to make it easier to locate the type of app you're after.

Currently all apps in the Android Market are freebies, which is likely to continue until the finer points of payment agreements have been ironed out. That doesn't mean there's any lack of quality, though, with plenty of genuinely handy apps available like iSkoot for Skype access, MySpace Mobile and the ShopSavvy barcode scanner price comparison app.

Downloading is simple, and once you've installed you're free to rate the app from one to five and add a comment for the benefit of potential users. It may not revolutionise the face of mobile apps overnight, but the Android Market is certainly one to get excited about for the future.

BlackBerry Application Centre

RIM is planning a two-pronged assault on the world of mobile applications, with a carrier-hosted Application Centre debuting on the newly available BlackBerry Storm and a centralised RIM Application Storefront launching in March 2009.

The Application Centre is essentially a list of apps that have been given the green light by the handset's carrier network (in the case of the Storm, Vodafone) and retrieved from RIM's server. Of course, this gives the network complete control over what's on offer, so it's unlikely you'll see too many apps that compete with Vodafone's interests.

The current list is made up of functional freebies, with social networking and IM apps dominating proceedings. Instant messenging apps include Windows Live Messenger, Google Talk, Yahoo Messenger, AIM and ICQ, but aside from this only Facebook and Flickr join the party. Of course, the arrival of more paid-for apps is inevitable as developers spring into action, but the involvement of the network in selection is a drawback.

More promising is RIM's Application Storefront due next year, but details are scant as to its contents. The lure of an 80 per cent cut from the proceeds will no doubt prove sufficient incentive for many developers to proactively push apps for the platform, and will hopefully lead to a more densely populated store. As it stands, the Application Centre is a rival to the iPhone's App Store in name only.

Nokia Download!

It may come as a surprise to many, but mobile apps were alive and kicking well before the iPhone came into existence and, as ever, the Finns were at the forefront with Nokia's on-device storefront Download!. It's available on most Series 60 devices and some Series 40 handsets, listed in the Apps menu as either Download! or Catalogs. The offerings are categorised into Applications, Tones, Videos, Graphics, Games and News & Info, and depend on your operator and handset.

But the user experience isn't good. Exploring the range of the third-party apps present in Download! is a bit like scraping the crumbs from Apple's table – meagre and uninspiring are two words that spring to mind. The interface is similarly poor, with app descriptions telling you little about what you're getting and numerous delays incurred while the handset downloads content info.

Installation is also far from straightforward: multiple confirmation messages just get in the way, and an incongruous file management system makes it difficult to find your install files. Billing is usually carried out directly via your operator, although to new users this is not always clear.

Partnering the on-device storefront is a web store, primarily supporting N- and E-series devices. This is still very much a work in progress, with no pricing information available; instead apps are listed as 'Try for free', and you're then prompted to send a premium rate text on install.

Overall, Download! is a half-baked attempt by Nokia to provide some added extras that may have been acceptable pre-Apple's App Store, but looks distinctly amateurish now.

So it's a two-horse race

For those who have experienced the delights of Apple's App Store, the Nokia and BlackBerry app outlets on trial here pale into almost embarrassing insignificance. Nothing can match up to the sheer volume of useful (and useless) apps on offer by the Apple's App Store, and the fact so many of these are free should also be applauded.

Not only that, but the one-touch ease with which applications can be downloaded from the App Store really shows what can be done when a bit of thought goes into the interface design.

Only the Android Store can match up to Apple's App Store in terms of potential, but this is yet to be realised and we'll have to wait and see whether Google can add it's golden touch once developers get into full swing. For now it's game, set and match Apple.

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Now read TechRadar's top 15 App Store iPhone downloads

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