Freeroc I didn't found the happycast in my x9. Could you to point me to a link for downloa or another source?
It's a third-party app. You can download it from here:http://www.hpplay.com.cn/update/happycast_tv.apk or you can try https://www.iezvu.com/os_download.php?l=en
AirReceiver I have had the greatest success with. Actively under development with frequent updates. https://play.google.com/store/apps/details?id=com.softmedia.receiver