The iPad app that puts a symphony at your fingertips "Every button you add, you take away clarity," says designer Matt Aitken as the production team debates the layouts. Max Whitby, the chief executive, decides that simplicity needs to be the priority: "Let's just do one thing really well." Work began on The Orchestra in September 2011, when the Philharmonia spent a day performing while cameras captured them from every angle - even from directly above. Now the app is finished, at a cost of around £250,000, and available from the iTunes Store for £9.99. Putting together the many elements wasn't an easy task says developer Richard Zito. The trickiest part is the music notation because the notation software isn't really made for this purpose. We had to force Sibelius into behaving the way we wanted it to and then from that we ended up with one big image of the entire score. Dealing with the sheer size of that [the score], dealing with adding metadata to it to know where every single note is and every single bar is and doing this in a way that's repeatable... was a significant amount of prototyping work. Though stories abound of bedroom developers who become millionaires as the app turns into a surprise hit, the real drivers of the apps boom are small agencies producing their own apps or making them for big name brands. More than three quarters of the top app makers are small businesses, according to a recent survey. A study by TechNet estimated that 500,000 jobs have been created in the 'apps economy' in the US since Apple and Google opened their mobile app stores in 2008. In Britain, recruiter ReThink says that app developers are now earning more than web developers; an annual salary of £70,000 is not uncommon, the firm says. That's because apps are becoming big business. Analysts IHS Screen Digest expects smartphone and tablet apps to generate revenues of £4 billion this year. Apps have "really made mobile media mainstream," says Jack Kent, media analyst at IHS Screen Digest. We expect that Apple and Google will continue to lead that market. He adds: "There has definitely been a shift where publishers are looking to release fewer apps with a focus on quality." Touch Press clearly focuses on quality but it also charges more than most publishers. It's apps are generally priced at around £10 - still less than a coffee table book but, Kent says, against the trend of the market, which is moving towards 'freemium' apps - free downloads with extras that can be paid for. Touch Press, says Whitby, is "striving to create a sustainable market for very high quality titles at a fair price." Another area in which Touch Press bucks the trend is by staying as an iOS-only developer despite the growth of Google's Android operating system. Many Touch Press titles demand very high performance from the CPU and graphics system. The Orchestra is a case in point. Many Android devices simply could not cope," says Whitby. Then we have concerns about the hardware inconsistency between devices and the plethora of installed OS versions. However, he adds that Touch Press has no "philosophical objections" to Android. When Touch Press launched its first app, The Elements, to coincide with the release of the iPhone, Stephen Fry said it was so good that it was worth the price of an iPad by itself. There are likely to be plenty who would make the same claim for The Orchestra.