Have you noticed that sometimes cell phone are not as smooth as it used to be and there is a bit of lag? Here are few tricks to help you out. 1. In every one week you should power off and restart your cell phone at least. If you restart your phone, it gets rid of all unnecessary temporary files and caches from the phone. 2. If it doesn't help then you can do a complete factory reset but do a complete backup before you do a factory reset otherwise you will lose all the data. In this way, all the corrupted files are deleted and you phone works like magic.