Not a successful startup but a successful product. I launched https://www.ghostnoteapp.com in 2015 and it's going really well. Releasing a new version 2.0 and expanding with chrome extensions to allow you to annotate even more specific items.
>Not a successful startup but a successful product.
What does that mean exactly? Lots of downloads/customers but not enough to be profitable (or not profitable enough to where it was worth the time and energy)?
Or is it profitable, but you just don't view your single product as a "start-up", because maybe it is a one-man-show, and not something you do full time?
The latter. It's profitable but I don't consider it a startup as it's "just a product" perhaps at one point when I have expanded the product line enough I would consider it a startup but for now it's just a nice relatively profitable product.
Thanks to HN it became a pretty good success. The original Show HN is here https://news.ycombinator.com/item?id=9145007