All of the iPhone and IOS computers are good at managing memory as you use multiple applications. Sooner or later if you're a heavy user of large applications you can fragment and use up all the memory in your phone and it can get slow.
One alternative is just to reboot your phone but that can take a good long while and when you're on the go you don't want to spend that time clearing out the memory on your phone.
A good alternative which I just learned about is this little trick. Press and hold the power button until the phone gives you the option to slide to shut down. Don't shut down. Instead. Press and hold the home button until your phone returns to the home screen.
By doing these steps you'll cause your phone to reset its memory keeping a list of all the existing running applications when you double click the home button so you don't lose that information like you would if you reboot. But the memory will be clear and your phone should run a little faster.
So it's a quick way within ten seconds to make your phone run faster by clearing out the existing memory. We’ll have a link to an article on our website that explains how to do this in detail. But it's really just those two steps.http://www.makeuseof.com/tag/speed-up-your-iphone-by-manually-clearing-the-ram/