What version of OS X should be targeted at my program?

Question

We are creating an application for OS X, and we cannot rely on our users, all upgraded to Snow Leopard, or whatever in the latest version. We want as many people as possible to use our application, but we also do not want to discard some of the improvements that were made in the OS X version, if only more than 1% of users are stuck using earlier versions.

Where can I find information on the proportions of people using each version of the OS? Or is there some kind of “common wisdom” in the problem that real Mac developers know?

We don’t need any add-on graphics or 3D animations, just old window APIs, but we already faced one problem when "NSStreamDelegate" is not supported before the snow leopard.

Thank!

Answer 1

Web statistics from Quantcast , end of February 2010.

North American statistics, but may serve as a guide.

Version    %
10.6    27.3
10.5    52.1
10.4    17.2
Other    3.4

Omnigroup also provide some useful insights into the updates of their installed base. You can click to see a breakdown of major and minor versions on your site. In July 2010 they:

Version    %
10.6    53.3
10.5    21.0
10.4    25.6
Other    0.1

Answer 2

, - Powerbook G4. Tiger. , , ( ), , 10.4!

, , , 10.5. , , , 10.4, .

Answer 3

NSStreamDelegate, (.. NSObject) 10.3. Apple , Objective-C 2 @optional.

, , , 10.6.