From what I can tell right now, iOS versions of the MS Office apps (eg Word, Excel, PPT, Outlook) are not enabled with Copilot for the iPhone. For the iPad, I do see Copilot enabled in the iPad Word app, but not the others.
It’s odd because there are a couple of YouTube shorts that show examples of Outlook on the iPad using Copilot as well, but it clearly does not work for me. Only Word for iPad has the Copilot icon activated.
On the PC platform version of all the apps, I see Copilot is enabled, and the web apps versions (where you access via the browser interface) for these apps also work with Copilot.
So I guess that’s the long way to say, I think Copilot still will take some time to be rolled out to all platform versions of the apps and the only place where I see it is reliably integrated is on the PC and online web platform.