If you only want to share(i.e. pin on a user board), then you can use iphone-URL-Scheme and call the Pinterest application along with the parameters url(URL of the page to pin), media(URL of the image to pin) & description(Description of the page to be pinned). Present a UIAlertView and forward them to appstore to download the official Pinterest application if the user has not installed it.
Reference:
http://wiki.akosma.com/IPhone_URL_Schemes#Pinterest
Code to open Pinterest Applicaiton:
NSURL *url = [NSURL URLWithString:@"pinit12://pinterest.com/pin/create/bookmarklet/?url=URL-OF-THE-PAGE-TO-PIN&media=URL-OF-THE-IMAGE-TO-PIN&description=ENTER-YOUR-DESCRIPTION-FOR-THE-PIN"];
if ([[UIApplication sharedApplication] canOpenURL:url]) {
[[UIApplication sharedApplication] openURL:url];
}else {
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Pinterest" message:@"Would you like to download Pinterest Application to share?" delegate:self cancelButtonTitle:@"Cancel" otherButtonTitles:@"Continue", nil];
[alert show];
}
UIAlertViewDelegate Method
- (void)alertView:(UIAlertView *)actionSheet clickedButtonAtIndex:(NSInteger)buttonIndex {
if (buttonIndex == 1){
NSString *stringURL = @"http://itunes.apple.com/us/app/pinterest/id429047995?mt=8";
NSURL *url = [NSURL URLWithString:stringURL];
[[UIApplication sharedApplication] openURL:url];
}
}