An app whose only novel idea is that the messages and photos you send delete themselves after some time, except for the fact that once they're in your friend's phone, they can of course take a screencap, or just have an app installed to store them... so the whole idea is based on cluelessness about basic security... and yet, there it is.
Tons of people use the app. The interface is central to its virality. Snap's growth wasn't a problem until Facebook did everything they could to clone it. Snaps failing because everyone is starting to realize that if you aren't GOOG or FB, you aren't worth spending $$$ on. Just the other day I saw an "OfferUp" ad on Snap that looked like a 90s banner ad. I can't tell if Snap went full self serve or if they are struggling to find people to buy on their platform. And who would after advertisers have been spoiled by FB's demographic data and GOOG's intent data?
Edit: I feel like I spend a lot of time defending snapchat when I hardly use the app.
But than again if we look at their finances (and stock), they have always been in the red and are resorting to selling glasses and hotdog costumes now (huge losses).
So maybe they aren't that successful after all.