Hi,

My Web search skills have deserted me. All I am after is a step by step guide on how to publish an app, made using Unity, on a Mac Mini, to itch.io

I did have an Apple Dev license, which cost almost $90 and I made nowhere near that much back, so renewing the license is not an option, 

I have uploaded some Windows and Android apps to itch.io and would like to make my Apple games available there as well.

Thanks in advance for any advice or suggections, or hopefully a link to a step by step guide...!

try https://cocoon.io/ it helps make ios apps (free version is limited file size), as far as testing i can't help you. Apple is very strict with apps running outside their products. If you wanted to test the app without apple's help (PC to iphone/ipad), you will need to jailbreak but that will break the warranty and if your phone/ipod breaks it will not be fix by apple.

you can download an app called “Unity Remote 5” it’s (on the App Store, the App itself is by Unity Technologies) and you can plug your iOS device (iPhone iPad into it) and... there are detailed forums on how to set it up but it’s super easy I do it all the time since I don’t have Apple dev, but basically you press play I the editor and the game starts playing on your iPhone/iPad. Not e you so have to have the build set to iOS, but that is easy.