//应用 URL Schemes
NSURL *url = [NSURL URLWithString:@"xxxxxx://"];
if([[UIApplication sharedApplication] canOpenURL:url]) {
//打开url
[[UIApplication sharedApplication] openURL:url];
}else {
NSLog(@"app store下载");
//App Store应用id
NSString *appID = @"1225825711";
//调到App Store应用界面
// NSString *str1 = [NSString stringWithFormat:@"http://itunes.apple.com/us/app/id%@",appID];
// [[UIApplication sharedApplication] openURL:[NSURL URLWithString:str1]];
//跳转到评价页面
NSString *str2 = [NSString stringWithFormat:@"itms-apps://itunes.apple.com/WebObjects/MZStore.woa/wa/viewContentsUserReviews?type=Purple+Software&onlyLatestVersion=true&pageNumber=0&sortOrdering=1&id=%@",appID];
[[UIApplication sharedApplication] openURL:[NSURL URLWithString:str2]];
}