Will IOS Eventually Allow Full Screen XCloud/Remote Play in IPhone and Ipad?

The iPad is a 4:3 screen,iphone is close but not quite. Xbox games are 16:9, and the games are designed to be run in that screen shape. If you wish to fill the screen, you need to use a 16:9 device

Hello there!

Unfortunately for the moment we do have any information of when this will be updated for you to able to use full screen on your devices. You could try checking with your device's support so that they give you more information.

Microsoft is getting back into the smartphone market, but with Android as its OS instead of a slimmed-down version of Windows. That probably is a significant reason why Android is getting the XCloud beta first, but Microsoft isn't foolish enough to ignore
iOS. I will be curious to play this on my iPad or iPhone.

I’m using my iPad or iPhone remotely when I play games. No HDMI cable. I reset network settings on my Xbox/iPad as well. No luck.

Unfortunately there’s no way to completely disable the headset on the Xbox, as it automatically assumes a headset is plugged in as soon as I start remote playing on my iPad or iPhone. As soon as I stop remote playing, it goes back to normal.

Apple requires all controllers to hold an MFi certification
(Made For iPhone/iPad) to be recognized and work properly with all iOS and tvOS devices. Without this certification, any games that have been built via Apple’s specifications and that you would like to play will simply ignore uncertified controllers
even if you can manage to pair it with iOS or tvOS.

I’d suggest that if you want to use a controller with your iPhone or iPad that has an MFi certification.