Performance optimization of an iOS App includes efficient memory management, reduction of unnecessary background tasks, and optimization of graphics and animation. In finding performance bottlenecks and memory leaks, Instruments should be used-a profiling tool in Xcode. Developers can do some more performance enhancements by minimizing heavy resources like large-sized images and also keep tasks running asynchronously. Testing on a regular basis on different devices ensures that the application works on all types of different hardware.