If you’ve missed the previous parts and would like to check them out, you can review what I wrote about Twitter apps, Facebook apps and games, URL shorteners and certain kinds of social platforms, and sites that help you tell a story, monitor your social analytics, and reach out to users willing to spread your message. For further reference, here’s a link to the amazing (and mind-boggling) infographic put up by Business Insider that shows no fewer than 28 different categories of social media marketing. Just in case you’re keeping score, I’ve covered nine of these in the previous articles, and …