Adrenaline is an eCFW that via taiHEN can do more amazing stuff than older eCFW hacks did. Apart from getting XMB, being able to play homebrew, PSP games and simply use your PSVita as a PSP, you can make use of various other features. These are the features that Adrenaline brings to the table:
Screen filter support
Save state support (even works for PSX games)
PSX support
64MB support
Ability to use USB Mode to access ux0 via the PSP emulator
Plugin support
Ability to use the Vita’s right analogue stick with games if they have a plugin that enables this. Camera Patch Light has a whole slew of patches to make best use of the right analog stick in PSP games
Ability to update Adrenaline via the Network Update feature in XMB
Much more (and more may come in the future since ‘TheFlow’ kinda doesn’t really like to stop developing for the Vita)
Further installation instructions and change log
Download link (can be used to update manually just in case something goes wrong)
Adrenaline Easy Installer v1.11
Source
Screen filter support
Save state support (even works for PSX games)
PSX support
64MB support
Ability to use USB Mode to access ux0 via the PSP emulator
Plugin support
Ability to use the Vita’s right analogue stick with games if they have a plugin that enables this. Camera Patch Light has a whole slew of patches to make best use of the right analog stick in PSP games
Ability to update Adrenaline via the Network Update feature in XMB
Much more (and more may come in the future since ‘TheFlow’ kinda doesn’t really like to stop developing for the Vita)
Further installation instructions and change log
Download link (can be used to update manually just in case something goes wrong)
Adrenaline Easy Installer v1.11
Source