If you own a controller (Xbox or PS4/PS5), pair it via Bluetooth. PPSSPP has native controller mapping. This elevates the experience from "mobile game" to "console-like."
However, the gaming community has found creative ways to experience Modern Warfare 3 (MW3) on mobile devices using various emulation and modding techniques. This guide covers how you can technically achieve this. 1. The "Modded ISO" Method (PPSSPP)