This is the key to unlock CAUSTIC to full version mode. The full version enables song saving as well as exporting to WAV, Ogg and MIDI. MAKE SURE YOU'VE TRIED CAUSTIC ON YOUR DEVICE BEFORE PURCHASING THIS. THIS WILL NOT UNLOCK VERSIONS PRIOR TO 2.0.0 PLEASE UPDATE YOUR APP IF YOU ARE ON AN OLDER VERSION. Once installed, simply close the installer and return to CAUSTIC, it will be unlocked. (If you had already unlocked CAUSTIC v1.x, you don't need this unlocker.)