FanBox
The problem with famous folk interacting with their fans is that it is one-way – they do, we receive.
FanBox is 2-way. Fans have a sandbox where they can submit anything (within reason) to the celeb. The submissions can be thoughts, ideas, images, sounds… The can be public or for the celeb only. The celeb can ignore them all, or browse and experience. If they like something, they can respond privately or publicly.
The beauty of this idea is that fans will be inspired to contribute because of the mere possibility the celeb might see what they contributed. Because it is the official channel, it is possible the celeb will see what they provided. By occasionally interacting, the celeb will encourage more from their fans.
Problem fans can be permanently removed, and true fans wouldn’t want to risk that. Serial pests can be removed from FanBox altogether.