A winning calculation

Discover how a visual effects designer coded a beautiful calculator app.


The Modern Calculator


Calzy 3 is a 2018 Apple Design Award winner. This award celebrates the creative artistry and technical achievement of developers who set the standard for app design and innovation on Apple platforms.

Theres beauty in numbers. Just ask Raja Vijayaraman, a visual effects artist who, as well as working on 2010 Indian hit movie Robot, has created one of the most elegant calculators on the App Store.

Having built the first version of Calzy as a modern update to existing calculator apps – whose memory functions he couldn’t get the hang of – Vijayaraman continues to refresh and refine the app in pursuit of perfection. But there’s more to Calzy 3 than good looks. The app also makes it easy to save a result, figure out tax rates or round to the nearest pound.

In 2017, after learning to program in Swift, Vijayaraman even completely overhauled the app, adding a drag-and-drop function that pins calculations and a feature that spells out your results in dozens of different languages. The 33-year-old, who is based in Chennai, India, explains how he learned to code from a PDF book, and the basic approach every app designer should remember.

Raja Vijayaraman receiving his 2018 Apple Design Award.

What problem were you trying to solve with Calzy 3?
The default iPhone calculator was one of the apps I used most. I felt it would be nice to have a full mathematical expression and also wanted to be able to bookmark calculations for future reference. The latest version, Calzy 3, is the result of thinking about how a calculator could evolve with the newest iOS technology. I used drag-and-drop to redesign the common memory functionality, and 3D Touch to make the app feature-rich yet uncluttered.

What were the biggest challenges in creating your app – and how did you overcome them?
I didn’t have a college degree in programming or designing, so the programming was a bit challenging. This free PDF book called How to Think Like a Computer Scientist: Learning with Python helped me understand the basics. There were a lot of concepts I couldn’t fully understand – like classes, inheritance, object-oriented programming – but I could easily relate a few things to the app, like that I should get input as ‘float’, calculate using a function and save that data as a string.

The Calzy 3 widget keeps the app’s beautiful interface a swipe from your home screen (left). Label and save earlier calculations on the app’s history screen.

What turned out to be easier than you expected?
When I started this journey five years back, I had zero experience selling software. But I discovered that anybody can enroll in the Apple Developer Program and start distributing their apps around the world. That looked so simple and very easy to get started.

At what point did you realise that you could pull this all off?
The very first moment after I put certain UI elements in the Xcode Interface Builder and saw the app running on my iPhone.

What advice would you give your younger self?
Regarding programming: don’t overthink. You won’t grasp everything in the first instance. Accept the slow and steady approach, and believe you will be able to connect the concepts along the way. Regarding designing: it’s all about solving the problem and making the app feel and look good.

Whats next for you?
Right now, updating all my other apps to the latest iOS 12. Also, I’m very excited about the new Core ML 2 and ARKit 2.