Dailyy is a web app that lets users sign up to get daily template suggestions in categories like design and web development in the form of a daily newsletter. The app launched on producthunt on the 20th of March 2020 and currently has over 41 upvotes. So far, only one paying user but 39 emails in the database for people who were interested but didn't pay. I'm only selling because it's more demanding than I thought and I don't really have the time to work on it further.
Bubble.io, billflow, sendinblue