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By Gas Strategies

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Sum-o is a calculator, a clever beautiful calculator. Its interface has been hand crafted to enhance your experience using the full capabilities of the latest iOS. Sum-o is versatile; it reacts to on-screen gestures and device motion.

Our favourite feature is the background which constantly and dynamically changes depending on your calculation. Warm colours indicate a positive answer while colder colours are displayed as negative. Right-handed? Left-handed? no problem - personalise the interface to your preference! Simple, practical and smart; go ahead and experience calculus differently with Sum-o.

NEW in version 2.0:
- introducing the percent operation
- quicker to launch
- more than 10 smart colourful themes to choose from!!!

NEW in version 1.3: smarter than ever by constantly displaying the history of your current calculation!

NEW in version 1.2: Sum-o on your iPad!!!

NEW in version 1.1: swipe horizontally to show your calculations history!!!

What's New in Version 2.0.0

- Add % operation
- Add more than 10 smart and colourful themes !!!
- Decrease time to launch the app


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Customer Reviews

It crashes a lot. : (

I absolutely love the design of the calculator; however, it always crashes on my 5s. I can't even use it, so I give it 3 stars.

View in iTunes
This app is designed for both iPhone and iPad
  • $2.99
  • Category: Utilities
  • Updated:
  • Version: 2.0.0
  • Size: 4.7 MB
  • Languages: English, Arabic, Catalan, Czech, Danish, Dutch, Finnish, French, German, Greek, Hebrew, Hungarian, Indonesian, Italian, Japanese, Korean, Malay, Norwegian Bokmål, Polish, Portuguese, Romanian, Russian, Simplified Chinese, Slovak, Spanish, Swedish, Thai, Traditional Chinese, Turkish, Vietnamese
  • Seller:

Compatibility: Requires iOS 6.0 or later. Compatible with iPhone 4, iPhone 4s, iPhone 5, iPhone 5c, iPhone 5s, iPhone 6, iPhone 6 Plus, iPhone 6s, iPhone 6s Plus, iPhone SE, iPhone 7, iPhone 7 Plus, iPad, and iPod touch.

Customer Ratings

We have not received enough ratings to display an average for the current version of this application.

Top In-App Purchases

  1. Pack of Themes$2.99