I use Facebook for some hobby groups, and I only use Safari to view it… the other day my daughter and I were watching The Fast and the Furious movie and I started getting my feed full of all the cars from the movie… so we did some experiments saying words like KFC and beer while the screen was opened, and we started getting beer and KFC ads in the feed… i dont know if the app makes it worse, but it was certainly a bit of an eye opener