The 2015 interview at a start-up awards show linked [1] in the article is pretty interesting. Evan gives a few startup ideas who failed before he succeeded with Snapchat, how he initially marketed Snapchat with flyers in a local mall , and that the amount "his father was tired of paying" in Snapchat’s bills was around $5K a month.
[1] https://www.youtube.com/watch?v=R-UAjGVPFIE