iphone - Check iOS version at runtime?

Question

This is sort of a follow on from my last question. I am using beginAnimations:context: to setup an animation block to animate some UITextLabels. However I noticed in the docs that is says: "Use of this method is discouraged in iOS 4.0 and later. You should use the block-based animation methods instead."

My question is I would love to use animateWithDuration:animations: (available in iOS 4.0 and later) but do not want to exclude folks using iOS 3.0. Is there a way to check to iOS version of a device at runtime so that I can make a decision as to which statement to use?

Answer 1

Simpler solution for anyone who'll need help in the future:

NSArray *versionCompatibility = [[UIDevice currentDevice].systemVersion componentsSeparatedByString:@"."];

if ( 5 == [[versionCompatibility objectAtIndex:0] intValue] ) { /// iOS5 is installed

    // Put iOS-5 code here

} else { /// iOS4 is installed

    // Put iOS-4 code here         

}