Marco Arment provides a detailed breakdown of his sales figures for 2014 for his app Overcast. More interesting though is the benefits he mentions to being self-employed.

I can work in my nice home office, drink my fussy coffee, take a nap after lunch if I want to, and be present for my family as my kid grows up. That’s my definition of success.
— Overcast’s 2014 sales numbers by Marco Arment

Couldn't agree more.