Here’s a quick way to speed up your iPhone (or iPad) on the fly. Hold down the power button for 3 seconds like you are going to shut your device off. Instead of sliding to power off, hold down the home button until you see your apps again. Thats it!
This newly discovered trick (credit to South African blogger Marc Forrest) clears the memory on your iOS device without having to restart it and really does make a difference. Give it a try!