ios点击链接直接跳转到 App Store 指定应用下载页面

1. //跳转到应用页面  
2. NSString  *str = [NSString stringWithFormat:@"http://itunes.apple.com/us/app/id%d",appid];  
3. [[UIApplication sharedApplication] openURL:[NSURL urlWithString:str]]; 
4. //跳转到评价页面 
5. NSString  *str = [NSString stringWithFormat: @"itms-apps://ax.itunes.apple.com/WebObjects/MZStore.woa/wa/viewContentsUserReviews?type=Purple+Software&id;=%d", appid];    
6. [[UIApplication sharedApplication] openURL:[NSURL urlWithString:str]]; 
7. 必须在真机上才有效，模拟机上无效。

如果评论页面无法打开appstore，用下面这行代码

NSString *str = [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:str]];