While was never officially released for the PSP, a fan-made port exists that allows you to play it via the PPSSPP emulator on Android . However, for the most stable experience, you should consider official mobile versions. Sonic Mania on Android (Official & Fan Ports)
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You're looking for a download link for Sonic Mania on PPSSPP for Android. I can guide you through the process. Sonic Mania While was never officially released for