dear gunmaster, I am having the same issues now with apple. I use ue4.20 and have received the metal.completionqueuedispatch threat error just like you. Do you have a final, absolut solution to this issue? Otherwise I will try Metal 1.2 (even though When Building with Metal 2.0 my first app was accepted): I really would not like to spam apple with my ever crashing apps (PS: after adking apple About more Information they told my that it works on many devices, my iPhone 8 and iPhone 6s for example BUT it crashed on iPadAir(which uses the firs 64 bit A7 processor, lowest supported Hardware)