My iphone 5 is sometimes slow and sometimes fast? - 1

Sometimes when i'm using LTE my iphone 5 would slow down all of the sudden but then when i turn it off for a day its really fast. Is there something wrong with my iphone?

Added (1). How do you close your running apps in the app switcher?

Just clear your ram. Double tap home and delete all of the running apps in there.

Your fine should be fine, just that you might want to get the habit of closing your running apps in the app switcher(double-tap home button), this way will help as lesser things needs to be processed simultaneously.