I refused to install any apps for a really long time, resisted the temptation very well!
That is until someone posted a lost ugly duckling, who ran away because it was being made fun of... and that was it! The hormones took over, I felt so sad for it that I HAD to adopt it and install the app. if only to give the duckling a home... and that lasted like, 2 seconds. By the end of that day I was hooked.
I WILL NOT install the other apps, though. I've hidden them from my news feed so they don't flood my feed with updates for an app I don't even have.