What are some of the 'best traffic' sources that you referred to?
For example, for a music app/site you would get strong and qualified traffic from Facebook ads, targetted at users who like the artists and record labels you feature. Or you could look at Pinterest, posting album covers.
One of the best for me has been Medium, way more effective than any blog I ever had. Probably because of the built-in userbase, and the SEO efforts that any blog would have to take a huge effort to build up.
Traffic through Twitter are mostly spam in my experience (i.e. 0 seconds spent on page). Although if you can get a viral topic going, that is generally a little better.