The Success Is Adding Up: 12-Year-Old Irish Girl Tops Worldwide Amazon Store With App She Invented

Um... so we sort of wish we had this app when we were getting ready for our Leaving Cert Maths paper. The app, which was designed by a 12-year-old Irish girl, has just become the number one app worldwide on Amazon’s Android App Store.

The Irish Examiner reports that Calculator Plus was invented by Isabel Hughes and her dad, Aidan. The mathematical app is now the best-selling calculator app for the Kindle Fire tablet in the US and Europe, it’s been downladed over 2.5million times and it has just become the most downloaded calculator on Windows 8. Not bad, right?

So what makes Isabel’s app so great? Well it allows you to easily add and subtract fractions and it shows you every move you made to reach a calculation – so you can always see where you are in the middle of a sum.

Isabel came up with the idea for the app when she was doing her maths homework with her dad one day after school.

“We had a sheet of fraction problems to solve and it was taking forever, so I wondered if there was a good calculator for fractions available in the App Store,” said Isabel, who currently lives with her Dad in Washington.

“It turns out that there wasn’t so we sat down and made one that looked as realistic as possible. I never would have believed it would become a hit all over the world. All sorts of people have found a use for the fraction calculator – we have even been thanked by quilt makers who say that it has made their job much easier,”Isabel added.

Isabel's app is being credited with making maths more accessible to everyone

Aidan, Isabel’s dad, is originally from Raheny in Dublin and used to work as a software developer for Microsoft. He now heads up a company called Digitalchemy.

“The beauty of Calculator Plus app is that it remembers everything you calculate, which makes it perfect for running a bunch of tasks in tandem over a long period of time,” said Aidan.

“Again it came from Isabel and I bemoaning the fact that you lose everything when you turn a calculator off. Isabel has always had an intuition for seeing what epople actually want in programs. When she was nine she brought an idea to the developers of Microsoft’s Bing, and it was adopted into the search engine interface,” he added.