MacOSX Market Share
I occasionally get questions from scientific software developers about MacOSX market share visiting my site, it currently runs at 55% MacOSX, 23% Windows, 13% iOS, 4% Android, 4% Linux. However I am aware that readership is very scientific focussed audience and does not represent worldwide use. So I occasionally have a look at Statcounter to get a more general view as shown below.
The mobile market is of course much larger and there are an increasing number of Mobile Science apps but at the moment it looks like Desktop/Laptop still dominates science.