Apple has been pleasantly surprising users of the App Store by making many popular and expensive iOS apps completely free. There has been no official report from Apple as to why this is but it is thought to be in celebration of what will be the iOS App Store’s fifth anniversary on July 10.

Apple doesn’t appear to be promoting the free apps on the App Store currently, however free apps will quickly climb the Top Free Apps chart. It’s likely the majority of the apps, which have been made free today, will make it into the top list before long.

The Verge were the first to report on this earlier today noting that Infinity Blade II, Superbrothers: Sword and Sworcery EP, Where’s My Water, Badland, Tiny Wings, Traktor DJ, Day One, Over and Barefoot World Atlas had all been made free early this morning. Traktor DJ, a DJ app for iPad, usually the most expensive of the apps, would normally set you back £13.99. None of these apps have ever been made free before but plenty of others such as Fishing Kings and Sonic Jump have in Apple’s generous ’12 Days of Christmas’ giveaway each year. In the UK an app, television episode or song is given away every day for 12 days, beginning on Boxing Day each year.

When it opened in 2008, to coincide with the launch of the iPhone 3G, the App Store had around 500 apps, now there are over 850,000 available to download. Apple sent posters to reporters last week to publicise the App Store’s fifth birthday charting the staggering rise in the number of apps available and the amount of money paid out to developers. To date, Apple has paid developers over $6.6 billion. Over 50 billion app downloads have been made in the last five years. The first billionth download was made in 2009, the ten billionth download in 2011 and fifty billionth was made in May 2013.

A study showed last week that to make it into the top 10 paid applications on the iOS App Store, software must average around 4,000 downloads per day, while a top grossing app must earn £31,000 per day. Apps ranked in the top 50 must make £8000 per day.

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