IOS从一个APP跳到另一个APP

NSString *requestUrlString = @"dianping://shopinfo?id=1000";        
NSURL *requestUrl = [NSURL URLWithString: requestUrlString];
        if([[UIApplication sharedApplication] canOpenURL:requestUrl]) {
            [[UIApplication sharedApplication] openURL:requestUrl];
        } else {
            //没有安装应用，默认打开HTML5站
            NSString *keywords = [@"吃饭饭" stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
            requestUrl = [NSURL URLWithString:[NSString stringWithFormat:@"http://m.dianping.com/shoplist/219/search?from=m_search&keyword=%@",keywords]];
            [[UIApplication sharedApplication] openURL:requestUrl];
        }