Since they launched last July, iPhone applications have become one of the fastest - and most popular - technological innovations ever. There are thousands of simple and free apps, including ones that are altering the face of music.
It can create a virtual pint, electronic flute or whoopee cushion; help you to beat traffic while avoiding speed cameras; let you read the complete works of Shakespeare; control your home television from the office; tell you the time anywhere in the world; or simply guide you to the nearest place to purchase a decent latte.
In fact, there does not appear to be much (bar enhancing your love life or curing a hangover) that an iPhone app cannot do - and that is why it has become one of the fastest-growing technological innovations of recent times.
More than 25,000 have been created - often by individuals working from home - and they have been downloaded more than 800 million times from the online iPhone App Store. From Coldplay to Manchester United, institutions of every shape and size are scrambling to get a piece of the action. Even Steve Jobs, Apple's CEO, was surprised at the initial success, exclaiming: "I've never seen anything like this in my career in software."
Now Trent Reznor, lead singer in a band at the vanguard of bringing technology into the music industry, plans to take things a step further, creating an app that will transform the experience of being a Nine Inch Nails fan.
NIN: Access, which is awaiting approval from Apple, could be one way forward for a music industry decimated by downloading in recent years. The application, which will be downloadable free, will let users start multiple conversations with strangers at gigs, locate other NIN fans in their vicinity, stream music, download photos and upload their own remixes. It will create an NIN community orchestrated by the band itself - not by any record company and not via any of the many social networking sites such as MySpace or Facebook.
"People are going to steal your music whether you like it or not; it's out there, it's free," said Reznor in an interview with the Observer. "You're never going to make a lot of money selling records like you used to, that's a fact. It's over."
And if the latest research is anything to go by, access to music is exactly what iPhone apps fans are after.
A survey, carried out by comScore Inc - a marketing research company - found that the single most popular app to date is Tap Tap Revenge, which has been downloaded by a third of those using the App Store. The iPhone equivalent of the Guitar Hero or Dance Dance Revolution rhythm games, Tap Tap Revenge allows the reader to play or tap along to music and the company has already linked up to the likes of Reznor to customise versions of the game.The latest is Tap Tap Revenge: Coldplay Edition, released last week, which, should you be so inclined, allows you to tap along to 10 of Coldplay's greatest hits including Yellow and Viva La Vida.
The study found that the best - and generally most successful apps - utilised the iPhone's hardware, such as its motion sensor or GPS.
It also revealed that 12 of the top 25 most popular applications were games, including versions of classics such as Hangman and Pacman, while social networking applications proved popular.
"With the amount of downloads they've had since the App Store launched last July, it must be one of the fastest rising businesses since the launch of the internet," said David Rowan, editor of the newly launched Wired UK magazine. "What's good about the App Store is that there's quite a low barrier to entry, so many of these programmers actually have day jobs and are just working on these apps in their spare time."
Individuals can download the software, create their own application, and for a one-off fee of $99 (£68) register as a developer with Apple, and then have it stocked in the App Store. If they do decide to charge for their application, they can set the price, and keep 70% of the charge, with 30% going to Apple.
Most applications in the store are written by third-party developers. For some this has been a return to the early days of the internet, or even computing itself, when young aspiring developers could make a living from their bedrooms.
A major part of the App Store's success is down to its simplicity and pricing. Most of the apps are free or a nominal price such as 49p. As one developer puts it: "If an app only cost 49p, people don't mind if they only use it once or twice, and it's not even the end of the world if it actually turns out to be a bit crap."
Ross McKillop, who developed the MMS application, which allows users to send and receive pictures and video (frustratingly, the iPhone can't receive a picture text message, although the next model will rectify that), thinks the reason iPhone App has taken off is simple: "We've had mobile phones with internet access for years, but it was so sluggish and non-user-friendly that hardly anyone bothered using it."
Malcolm Barclay has a background in computers but is a self-taught programmer who saw a gap for an application that offered updates on the London Underground. "The idea doesn't have to be unique," he said. "It's not rocket science that you might want to be able to retrieve Tube information on your phone, it just comes down to execution. I just wanted to make it so simple and easy to use, and of course I made it free, so there was no reason not to try it."
After the success of Barclay's TubeStatus, he was deluged with requests to provide a fuller package including maps and a journey planner option. "I thought someone else would do it, but after a few months no one had, so I just did it myself." TubeDeluxe sells for 59p.
The concept took shape for Nine Inch Nails one night last summer when Reznor was "fooling around" with his phone backstage before a gig and noticed fans queuing to get in were already uploading pictures of the scene. "So we then communicated with them and said, 'We're backstage' and that freaked them out," explained Reznor. "But that got the wheels turning and we thought, 'How can we develop that?' "
The fact that NIN are not tied to a record label frees them to experiment with such new ideas. "Record labels do not know how to deal with the new media environment that they're confronted with," he added. "They've made their fortunes selling plastic discs and now no one wants to buy plastic discs - they're just trying to get their fingers in every other pie, but they're so greedy and ignorant they're not prepared to do what they have to do." The key to success, argued Reznor, is not to see the apps primarily as a way to make money: "All we're trying to do is make something cool. Something that as a fan you'd say, 'Hey, I want to have that'. If we can monetise it, then that's fine, no problem."
The notion of thousands of fans talking at a concert via their iPhone may sound hellish to old-fashioned gig goers. "On a personal level, I do find that kind of silly," agreed Reznor. "I tend to not take cameras on vacation any more as I want to experience that moment as a human, not as a documenter. At a concert, it's up to them, I can't tell them how to experience a concert. If that makes you feel like you had a better time, holding a phone up the whole time, then OK."
Naturally, Apple's competitors are keen to move into the market. The main competitors are Google Android Market, launched in October last year, for phones that run on the Android system, Nokia's Ovi store, and the just launched Blackberry App Store. Microsoft is also planning to launch a Windows Marketplace later this year. "Nothing keeps still for very long in this field," said Rowan, "and when you have a booming market dominated by one company, other people are going to look at it."
A few developers have made a small fortune, but McKillop has a sober word for anyone looking to cash in: "We certainly haven't made a fortune from our application. Although we have got a lot of other work through it. I believe the guy who created the iFart [whoopee cushion] is a millionaire though ... draw your own conclusions from that."