Maths for kids: iOS vs Android

It started this morning during a coffee break at the office. If you drop by one day, no doubt that you will attend passionate discussions between iOS and Android developers. Each team can argue that the platform they develop on is the best and why. But what about our users who are non-developers? Do they prefer iOS or Android?
A quick look at our database can give you the answer to this question. So, let's play with data. If you have a kid aged between 7 and 8, you can solve the following exercise with him ;)
Problem

89 of my friends have made an Android app.
78 of my friends have made an iOS app.
How many friends of mine have created:
- an Android app only?
- an iOS app only?
- an app for Android and for iOS?
Solution
Android only = 22
iOS only = All my friends - Android friends = 100 - 89
iOS only = 11
Android & iOS = All my friends - Android only - iOS only = 100 - 22 - 11
Android & iOS = 67
Conclusion
67% create the app for both Android & iOS
22% create the app for Android only
11% create the app for iOS only
Design

