Games look dark on xcloud using Note 10

Well the thing is you still need your xbox for xcloud

As it takes most of the proccessing your phone is only a display in No way would a phone ever have enough power to play games with hdr

Stradia and xcloud relies on cloud proccessing unlike stadia it's not paid service that requires you to buy games stadia requires more bandwidth because you are using google servers for power

Xcloud uses your local xbox and network and live

Xcloud only supports a limited amount of titles and gamepass only

It is upto the publisher to allow it

Should be noted that games take a significant performance hit using xcloud

There is no official announcement if xCloud will be available on iPhone but it is highly likely that it will the official statement is it will be available on "your phone, tablet or another
connected device" for more information on xCloud visit https://blogs.microsoft.com/blog/2018/10/08/project-xcloud-gaming-with-you-at-the-center/ and https://news.xbox.com/?s=xCloud

I think we can note the xCloud works on android platform so let see the next one. For instance the windows 10.

Thank you for your reply.

Also would be noted that only one account can use xcloud and that is ONLY the subscriber

That is up to the developer of the gare more than Microsoft, but don't worry, Project xCloud might be what you're looking for and it is coming soon: https://www.xbox.com/en-US/xbox-game-streaming/project-xcloud