I don't know how well it will work for others but, go to The Play Store for Android or the IOS for Apple.
It is called "Anymote" and it does work with some wrangling and trying it out.
I was looking for something else here as the new Xfinity update has disabled my Alexa from controlling my TV. Any help there is appreciated. The update was approx. 3 days ago. Anyone?
I agreee it would be great if alexa and google assistant could work with the X1 boxes. I have a Sony TV and it will power on/off and change channels with voice commands (either google or alexa) and it can control the channels on the X1 box with it's IR blaster, but it can't start or control apps on the X1. That is something that would really benefit from integration.