IOS:在app中访问appstore中的app

1、在应用内访问App Store中特定的app

float version = [[[UIDevice currentDevice] systemVersion] floatValue];    if (version < 7.0) {        [self openWebside:[NSString stringWithFormat:@"itms-apps://ax.itunes.apple.com/WebObjects/MZStore.woa/wa/viewContentsUserReviews?type=Purple+Software&id=%@", APPId]];    } else {        [self openWebside:[NSString stringWithFormat:@"itms-apps://itunes.apple.com/app/id%@", APPId]];    }