UIActivityViewController

Initializing the Activity View Controller

Objective-C

NSString *textToShare = @"StackOverflow Documentation!! Together, we can do for Documentation what we did for Q&A.";
NSURL *documentationURL = [NSURL URLWithString:@"http://stackoverflow.com/tour/documentation"];

NSArray *objectsToShare = @[textToShare, documentationURL];

UIActivityViewController *activityVC = [[UIActivityViewController alloc] initWithActivityItems:objectsToShare applicationActivities:nil];

[self presentViewController:activityVC animated:YES completion:nil];

Swift

let textToShare = "StackOverflow Documentation!! Together, we can do for Documentation what we did for Q&A."
let documentationURL = NSURL(string:"http://stackoverflow.com/tour/documentation")

let objToShare : [AnyObject] = [textToShare, documentationURL!]

let activityVC = UIActivityViewController(activityItems: objToShare, applicationActivities: nil)
self.presentViewController(activityVC, animated: true, completion: nil)

Parameters

Parameter Name	Description
activityItems	Contains array of object to perform the activity. This array must not be nil and must contain at least one object.
applicationActivities	An array of UIActivity objects representing the custom services that your application supports. This parameter can be nil.