Since 2017 and the introduction of the A11 Bionic SOC, Minecraft for iOS has been poorly optimized for the varying cores in the newer SOCs.  For example, older chips only have 2 powerful cores and the A10 Fusion has 2 high-efficiency cores and 2 high-performance cores, each can only be used together (either both performance or efficiency cores, not all four) don’t experience this problem because Minecraft is forced to run on the Higher end Cores. But with the A11 and newer, each core can run individually, all 6 can run at once. On top of that, there are 6 cores - 4 high-efficiency and 2 high-performance cores. Minecraft doesn’t know which cores to use an ultimately uses the weaker cores, resulting in a game that runs worse on newer hardware. I urge Mojang to fix this and work with Apple to allow Minecraft to run better on the newer devices. I have a recording attached below to this description since it greatly exceeded the stupid 10MB file limitation. The recording did not affect gameplay, the recording shows the real-life poor frame rate on newer devices.

https://drive.google.com/open?id=1ObXzgVZRZn61THZ68VYybgbSMJjZIqPs