Help for more traffic

Hi All !
I have started mobile phone forum and looking to promote it and need to get some quality contents from the real users of the forum.
I have added some links to sister sites but Only getting user signups, not the quality content from them. Is there any better idea how I can achieve my goal ?
My forum can be found here:

there are two solution's for your problem.

1. Do everything yourself.

2. Hire someone to do it for you (seo,smm etc)

let me know if you need any paid help i charge monthly and provide reports.cheers

I think its really a time taking and really very tough task.