NSURL *url;
// QQ
url = [NSURL URLWithString:[NSString stringWithFormat:@"mqq://im/chat?chat_type=wpa&uin=%@&version=1&src_type=web", @"QQ號"]];
// 微信
// url = [NSURL URLWithString:@"weixin://"];
// 電話
// url = [NSURL URLWithString:[NSString stringWithFormat:@"tel:%@", @"電話號碼"]];

if ([[UIApplication sharedApplication] canOpenURL:url]) {
    [[UIApplication sharedApplication] openURL:url];
}