If you type into Google, you will find a desert of broken links and suspicious torrents. The honest answer is: There is no native PC version.
MotorStorm: Apocalypse does not have a native PC version or an official digital download for Windows; it remains a PlayStation 3 exclusive. To play it on PC, you must use the emulator. Current Emulation Status Motorstorm Apocalypse Pc Download
He tried to Alt+F4. The keyboard was dead. He reached for the power strip. His hand passed through the switch—no, the switch was becoming transparent, flickering between this reality and a wireframe grid of code. If you type into Google, you will find
Because MotorStorm Apocalypse is technically demanding to emulate, you will need a modern PC to achieve stable performance. If you type into Google