If you want simple sharing, the following can be used for Twitter and Facebook:
if ([SLComposeViewController isAvailableForServiceType:SLServiceTypeTwitter]) {
SLComposeViewController *slComposeViewController = [SLComposeViewController composeViewControllerForServiceType:SLServiceTypeTwitter];
[slComposeViewController setInitialText:@"Your text"];
[slComposeViewController addImage:[UIImage imageNamed:@"NameOfImage"]];
[self presentViewController:slComposeViewController animated:YES completion:nil];
} else {
//Show alert or in some way handle the fact that the device does not support this feature
}
For Facebook, simply replace SLServiceTypeTwitter with SLServiceTypeFacebook. The "Social" framework must be imported :-)