Thanks for testing it, I knew that the advanced options didn't work on iOS, the problem is that they work for Desktop & Android (maybe it's a problem with the browser). I was hoping that it was only in my wife's phone, but I haven't been lucky.
The vectorization is probably where I've spent most of the time regarding creating a UI to tweak it. I already implemented two vectorization libraries, the results aren't perfect, but they are the best I could get with what I found. It would be great if anyone know a better technology (thanks in advance!). Great idea, using color palettes could fix the issue of having to tweak too many colors, I will put it in my TODO list!