“Windows changed my life” – How physics student Richard Walters got 500k downloads

Originally posted on the UK Students Blog.


Richard Walters is a pretty cool guy.

A Physics graduate from the University of Oxford, he’d never built an app – or even thought about it – until he got a Windows Phone and as a student encountered DreamSpark, a free way for students to get all the tools you need to build apps. He built his scientific calculator app, Calculator², for Windows Phone and now has over 250,000 downloads. Not only that, but he ported the app to Windows 8 and in just six months has – wait for it – over 500,000 downloads. It’s the singular most successful calculator app on the Windows Store. How did that happen?

Richard got his Windows Phone when the Windows App Store was still in its infancy. As a Physics grad, calculators were integral to his life. When browsing through the available apps, he was disappointed to find that the selection ‘back-in-the-day’ was not great. However, building the definitive calculator app was not what Richard set out to do. He thought, “if I could build a calculator, I could build anything.” Using building a calculator app as a means to test his skills, Richard inadvertently built the most successful calculator app to date. He had to start from scratch – whilst his PhD was very numbers-oriented, he didn’t know about object-oriented languages and had never used C# before. However, downloading and working with the tools for developing Windows apps was much easier than he thought it would be, and he found helpful online resources in such places as MSDN and stackoverflow.


Richard initially built the app for Windows Phone 7 and then extended his repertoire to Windows 8. “It was very easy for me to port my Windows Phone 7 app to both Windows 8 and Windows Phone 8. Particularly in the latter case, my code is 99% identical between WP7 and WP8, with the difference simply because of a few updated controls in WP8. At the moment I’ve duplicated the projects for the app for each platform, but one thing I’ll be doing over the next few weeks is setting up the code to share the same projects/files across each version so that it’s even easier to continue working on the app. Also, it was much easier than I had expected to handle the various screen resolutions and pixel densities in WP8 and W8.”


One of the biggest challenges for Richard was marketing the app. As he wryly observed, “as an independent developer, you can’t invest in marketing.” He initially released the calculator as a paid app with a trial. “This in theory should work well, but for new apps rarely does. If you publish a new app, it’s very difficult for you to get the ratings you need to become visible in the store.” He decided to release a free version with adverts to accompany the paid version without adverts. The free version has not impacted the sales of the paid version. On Windows 8 the app is free and ad-supported, but with an in-app purchase option to remove the adverts. He earns a lot more from the adverts and has had 30-40,000 daily impressions pretty much consistently since it was released. His marketing strategy included contacting WMPoweruser, WPCentral and various other community websites and cajoling them into publishing articles on his apps, as well as using social media methods like Facebook and cross-promotional premises like AdDuplex. “Often one article is enough to be a catalyst for a wave of responses; very often people will pick up on a new app and write their own reviews.”


Should he publish another app, it’s to his advantage that he already has a foothold in the market. He can advertise his new app in Calculator² and get a decent number of downloads off the back of his first insanely successful app. He’s looking forward to adding more features to his app, including a financial calculator and a graphical calculator for instance. “I imagine I’ll spend at least another year working on this app – a good exercise for my new job will be porting Calculator² to Android – before working on something new for Windows. My ultimate aim is to try my hand at developing a game.”


Richard attests his app’s popularity to its design. Before his app came along, the calculators in the app store were essentially clones of hand-held scientific calculators. “Mapping a traditional calculator to a phone screen is not a good idea, as the buttons are too small and mistakes are easily made without tactile feedback.” Richard threw tradition away by utilising the Windows UI and making the app in line with the phone itself. The Windows UI was particularly useful, as it strips away all the stuff that doesn’t need to be there. One of the tricky things was conveying the hidden buttons in the app, but not flooding the app with message boxes. Striking a balance was difficult, but gathering feedback from users has helped to continuously make improvements. “The primary function of the app is that it has be functional,” Richard said.

From Windows 8 design session to 500k downloads

He added all the features that aren’t used often in the app bar and incorporated live tiles – which show the calculation history – to allow the user to jump straight into different parts of the app. Specifically related to Windows 8 (along with live tiles) the snap mode is particularly useful as his app gets used often alongside other apps when doing calculations. The whole app can be navigated by keyboard and touch, complimented by the semantic zoom. He had no means of user testing the app during development, so relied heavily on his own instincts as to what worked best. He never wrote anything down or planned anything; it was literally a case of playing in Visual Studio to see what worked.

Richard didn’t have any preconceptions about working with Windows because he came to Windows 8 and Windows Phone with a clean slate. “The opportunity is definitely there to be successful,” he claims; evidenced in the huge number of downloads he has had since launch. He’s currently earning more from Windows Phone than from Windows 8; a lot of that is to do with the user base as a lot of people are much more used to buying apps on phones than they are on computers. “Hopefully that’ll change as more tablets get into the market,” he observed.

What also adds to this app’s success is its multi-functionality. Not many apps are calculators, currency converters andunit converters. Nor are all these modes calculators within themselves. The app doesn’t just convert one number to another, you can do a whole calculation within each mode.

App building gave Richard a new view on his career; while he was getting into app building toward the end of his PhD, he was becoming disenchanted with academia. He presumed up until this point in his life he’d continue to do scientific research in a research firm after finishing his PhD. From building the app he soon realised he thoroughly enjoyed software development and his eyes became firmly fixed on this as a future career. He didn’t know what his skill set was like compared to other people who’d been taught formally; he just knew he wanted to do it. 082

Richard once claimed “Windows changed my life” – and that’s not just relating to the success he’s had with his apps. “I went for an interview and as part of introducing myself started talking about my app building experiences. That conversation took up most of the interview and I felt confident afterwards that I had a good chance of being offered the job.” Richard now works as a Graduate Consultant Developer at ThoughtWorks.

“I would definitely recommend developing for Windows 8,” Richard said. “And Windows Phone is looking really good at the moment. The great thing about building apps is just designing something, having a play, and seeing the results instantly. Plus you learn a huge amount from the whole experience, not just in terms of how to code but also marketing, customer support, dealing with finances and much more.”

The US Windows team have been so impressed by Richard’s success that they flew him out to film his story – you can catch the video here (see Independent Developers).

If Richard has whet your appetite for some app development then here’s everything you need to get started:

Windows 8

>> Sign up for a Windows Store account
>> Download the Windows 8 SDK for all the free tools you need to get started
>> Build a Windows 8 app in 10 minutes with ZipApp

Windows Phone

>> Sign up for a Windows Phone store account
>> Download the Windows Phone 8 SDK for all the free tools you need

A guest post written by:

Laura O’Connor

A recent graduate in English Literature and Language from the University of Oxford, Laura O’Connor now works at Microsoft as an Associate Consultant in Unified Communications. She is currently immersed in Exchange, Lync and O365. Outside of  work, her interests lie far from the realm of technology; she enjoys going to the theatre, reading and writing.

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