Using (the premier PS2 emulator for Android), you can play the PS2 BIOS of Serious Sam 2 on your phone.
While Serious Sam 3: BFE and Serious Sam: The Second Encounter have seen official releases on mobile platforms, one question burns in the hearts of Android gamers daily:
Technically, yes. Because this method works exclusively on Android devices with Snapdragon 8 Gen 2 or newer chips. iPhones cannot do this easily. Users report 30-45 FPS on modern flagships like the Samsung Galaxy S23 Ultra or ASUS ROG Phone 7.
The closest thing to an official mobile version was a cancelled project from 2009 called Serious Sam 2: Android Assault (a top-down shooter, not the FPS). That game was scrapped before release. Do not download any APK claiming to be "Serious Sam 2 for Android Exclusive full version" from random websites. 99% of these are malware that will steal your contacts or show infinite ads.