ATTENTION: ONLY FOR iOS 3.1X - 4.2 All right, so first off, download iMemory Enhancer from the insanelyi repo. If you don't have it, go to Cydia and then Manage>Sources>Edit>Add>repo.insanelyiph0ne.com. After downloaded, respring your iDevice. Then go swipe your status bar at the top for the SBSettings. If you don't have it, download it from the Search icon on Cydia. Then when you're on the SBSettings, click "Processes", and then "Free up memory". Then, look at your available more at the bottom of the SBSettings. It should have more than it had before. Good luck!