IPhone 4 already out of data?

My iPhone 4 only has a little bit of data left and that's frustrating because I have only 130 pictures (no videos) 2 social networking apps and two other apps. (I've deleted things from those apps too) and I only have 30 songs at most. And hardly any contacts. But I only have 6ish gigabytes. What can I do to get more memory/ delete to have more memory.

Well, first you could upload your pictures you do have on a computer so you can have that space, also whatever gigabyte iphone you have is a lie because those gb are also used for the phone itself, also if your phone can use micro sd cards or other extra sourse of gb you could do that, sorry, hope this helps