// 应用网址 返回字典中有多种数据
NSString *urlString2 = [NSString stringWithFormat: @"%@", @"http://itunes.apple.com/lookup?id=应用ID"];
NSDictionary* infoDict =[[NSBundle mainBundle] infoDictionary];
NSString* key =[infoDict objectForKey:@"CFBundleVersion"];
// 如果有新版本 使用UIAletView显示
NSString *newVersionUrl = dic[@"trackViewUrl"];
[[UIAlertView alloc] initWithTitle: @"新版本可用" message: dic[@"releaseNotes"] delegate: self cancelButtonTitle: @"稍后更新" otherButtonTitles: @"立刻升级", nil] show];