1、获取app 在AppStore上的网址
eg：
NSString * appURLStr = @"https://itunes.apple.com/cn/app/shi-ke-zu-qiu-bi-sai-zhi-bo/id1071662346?mt=8";
2、将字符串替换
eg：
appURLStr = [appURLStr stringByReplacingOccurrencesOfString:@"https:" withString:@"itms-apps:"];
3、跳转到AppStore
eg:
[[UIApplication sharedApplication] openURL:[NSURL URLWithString:appURLStr]];
注意事项：必须在真机上调试！