Excerpt from this article:
Together, the referrers suggest how people tend to shift from site to site throughout the week. While it still doesn’t matter when you publish, you might share your posts at different times and places depending on your audience. Twitter is more popular earlier in the week, while Facebook is more popular mid-week. LinkedIn and Gmail rise in the early mornings and after-lunch hours, whereas Reddit and Hacker News peak after dinner. Google search and content aggregators are more consistent throughout the week. And on the weekend, we’ve got you covered on the Medium app.