I recently upgraded iOS in my iPhone device to 12.2 (to provide support of latest versions for my app \"Match4app\"), and this does not appear to be compatible with Xcode 10
None of the above helped for me.
I was able to install Mojave using this link here: http://dosdude1.com/mojave/ This patch worked beautifully and without a hitch
Proof: here's Mojave running on my (unsupported) 2011 Mac-mini