I remember last year there was so many users using viral apps on Facebook, but lately I see no one using this anymore on my newsfeed.
What's the reason?
The reason is simple.Facebook added a new feature to limit spamming of content. the new feature means when someone deletes content from their wall that you posted.facebook takes this to mean the person is unhappy with the app.so in otherwords. when you have an app going viral but 10% of people remove your post.facebook now restricts your app and you loste all virality immediately. it dies then and there.the end.
rofl..new feature? facebook has had that forever
99.9% of app deletions and restrictions have nothing to do with user feedback, but things like too many API calls, or making the aps on bad IPs and stuff like that