Mobile internet help?

[Mastertiger766]

Hello to all of you!
I'm thinking of getting a package for mobile which includes 500 minutes for talking and 500 messages (they aren't that important to me) and 1gb of mobile internet, which is much more important for me. (I get these messages, minutes and gb each month)
So, I like using apps like FB, Twitter, Instagram and so on, so is 1gb enough for me? And if, for example, facebook is running in the background (I have an iPhone, Idk if this is even possible), will that lower this 1gb much? Will it affect at all?
Thanks so much in advance.

[lawman]

1gb is enough if fb,whatapp or any other social networking app is running in back,because these apps consumes data whenever any message is sent by your friends.
Messages consumes less data as compare to downloading&watching any video online.if you watch any video online then data will b consumed in high quantity.
If you have smartphone then in network setting there is data monitor through which you can check how much data is used by your phone &which app consumes how much data.