You might need to tweak the emulator settings to achieve smooth gameplay. Adjust graphics, sound, and control settings according to your preferences and device capabilities.
This phrase combines several misleading elements. GTA V is a modern, commercial game made for PC and consoles; there is no legitimate, official “PPSSPP ISO” version of GTA V for Android. PPSSPP is a PSP emulator and runs games originally released for the PlayStation Portable (PSP). GTA V was never released for PSP, so any site claiming a “GTA 5 PPSSPP ISO” is almost certainly distributing an illicit or fake file.