SimilarWeb is a tool that tells you where websites get most of their traffic from. If I wanted to build a competitor to Todoist.com, I’d go to SimilarWeb, type in “Todoist.com,” and this report would generate: I immediately learn that the majority of Todoist.com traffic comes from LifeHacker.com and Ifttt.com. Go make friends with the CEOs/authors of those blogs/websites. It’s a double whammy to persuade those people to write about your new tool while at the same time hurting your competitors’ traffic.