Considering that it's a 3-1/2 year old phone, designed to run Gingerbread, it's to be expected that it's going to be laggy with current apps. They're designed to run on phones with at least 2GB of RAM and your phone has 512MB of RAM. So there's lots of app killing and loading as you do things (kind of like Windows swapping programs to the hard drive when there's not enough RAM). There's no way to "fix" it. Most phones work well for about 2 years, flagships may hold up for 3 to 3-1/2 years, but eventually all phones "run out of steam" and have to be replaced even if they're running well otherwise. (I still keep a Motorola V-551 running, just in case I need a cheap-to-replace phone in a hurry. It makes phone calls. It even has a camera. [It was one of he first phones to have one.] But I wouldn't think of using it as my daily driver.