iOS Simulator games run very slow (low fps)

Solution 1:

The Simulator is not a device. The Simulator uses the Mac's CPU (tons faster) and the Mac's memory (lots more). However the Simulator also emulates OpenGL ES via a software renderer, which is abysmally slow even on the fastest CPU.

Because of this and the fact that no end user will ever run an app on the Simulator, any performance measurements on the Simulator are utterly IRRELEVANT!

Sorry for shouting but I felt this needed to be said with conviction. ;)

Solution 2:

Even though this post is almost 8 years old I found myself in the same situation when trying to record an App Store preview for my Unity game.

With your simulator open you can change the GPU Selection to improve performance. It was set to Automatic for me and changing it to Prefer Discrete GPU dramatically improved the frame rate.

Notes

• Tested with Xcode 12.5 - not sure when this feature was introduced.
• I had to restart the simulator for it to take effect.
• Your Mac will presumably need to have a discrete GPU in the first place (mine is a 15" MacBook Pro).