I've got a Macbook 12 (2017), and it's surprisingly fast - I think it's definitely viable for iOS app development, as long as you have it hooked up to an extern

I've got a Macbook 12 (2017), and it's surprisingly fast - I think it's definitely viable for iOS app development, as long as you have it hooked up to an external screen. I find that Xcode is a little cramped on the notebook screen if you have all of the panels open, but if you can close at least one of them, there's enough room to work. I only have 8 gigs of ram in the Macbook (I have a Macbook Pro I use as my daily driver with 16 gigs), and that seems to be fine with Xcode, as long as I use Safari instead of Chrome, and don't keep Android Studio open at the same time.