Re: "as well as following and unfollowing those who don't follow back"
I think we all know what Twitter means with this. They are protecting against the practice of building a follower list by following a bunch of people, waiting to see who follows back, then bulk unfollow those who did not follow back, to make "room" so that you can follow more, and repeat the process. All I wanted to say with my original post, was that apps that do bulk unfollow are at risk or are putting their users' Twitter accounts at risk, because they are enabling those Twitter accounts to do "following churn". At the very least you need to warn your users that such action is putting their accounts at risk. And Twitter should add this to their Twitter Rules so that more users can become aware of it. There are "gurus" out there who are charging ignorant folks for ebooks and advice that teach them to do exactly this, namely following churn. And those folks don't know better because right now those rules (terms) are not very clearly spelled out in the place where most people would look for them.
