Apple's App Store is about to hit 50 billion downloads.

The counter is ticking down at the rate of about 1,000 apps per second. (Apple actually claims that over 800 apps are downloaded per second.)

What are your chances of buying the 50 billionth app? When should you purchase an app to give yourself the best chance of winning?

As of 10:38 the counter showed 49,914,547,224.

Working on the assumption that the 1,000 downloads shown by the animation is accurate, Apple will reach 50 billion downloads in about 85,400 seconds. 

That's based on the assumption that selling the remaining 85,452,776 should take 85,452.776 seconds.

85,400 seconds is almost 24 hours.

So we estimate that Apple will sell its 50 billionth App at about 10am GMT tomorrow morning.

Of course, given that the knowledge that the end is in sight means that more people could be purchasing App Store apps today, and once the US wakes up the sales will reach fever pitch.  

For that reason we would recommend purchasing your winning app at around 8am tomorrow morning.

There you go. A completely unscientific calculation that will most likely not mean you win the $10,000 voucher Apple is giving away with the 50 billionth download.

Still, it would be nice if someone from the UK won.

Incidentally, according to analyst Horace Dediu's calculations, iTunes users spend at the rate of $40 a year, so that $10,000 voucher should keep the lucky winner going for 250 years. 

Follow Karen Haslam on Twitter / Follow MacworldUK on Twitter 

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