I've written a children's book, which I plan on self publishing as an app. I have a built-in mode of marketing, which should ensure publicity for the book.I'm afraid I don't know. I've never worked on a self-published book. Regular publishing pays illustrators thousands (or tens of thousands) of dollars, plus royalties. And if we pay an illustrator on a flat-fee basis, even then they'll have a publication credit to point to that can further their career.
What should I expect to pay the illustrator? What are the standard fees asked for by an illustrator in the self publishing arena?
Of course, most of the self-published books I've seen weren't professionally illustrated, and that's one reason they sell so badly. If you were thinking of going to someone of professional quality, I don't know what kind of money would tempt them to work on a self-published book.
If you weren't planning on that, you have bigger problems than what you'll pay them.