If you don’t know what PSM games are, they’re games that used to be available via a service that closed over 3 years. Unfortunately, this meant that there was no longer a way to play them (unless you had bought them and they were on Vita already) but then, frangar released NoPsmDrm which fixed this problem. However, modding these games was impossible since NoPsmDrm didn’t decrypt the game itself but only created fake licenses to run the games. Thankfully, a few days ago F*PSSE was released and this decrypted PSM games and their files so that you could modify them. Now, PSMPatch has been released and this lets you install mods to PSM games such Cytus Lambda and also run PSM homebrew! Among the realistic stuff that you can expect to come out of PSMPatch, we find:
Patches to unlock content that required you to make an IAP
While this may be illegal, it’s very difficult to make a case against it because the servers for processing these IAPs have been down for years
Mods that could change the look of certain game elements
Ability to make homebrew PSM games/applications with the PSM SDK (which means that you can code in C# for the Vita)