Research on websites for dating, making friends/contacts and buying/selling services

General information for the business: I am researching this field to help conceptualize my idea for a startup Geographical areas: I'm in Paris and NYC, you can be anywhere Data to include: I want to brainstorm over video chat regarding your personal experience using dating sites and apps, other types of sites where you meet new people, and sites where you buy or sell services, such as craigslist along with this site right here. Extra notes: For what it's worth, I am an entrepreneur who has launched over a dozen companies, most internet, most failed, but a few that reached millions of users. I see starting this job with just a 1-2 hour work session. This could lead to much more work.