Why isn’t there? Well, it takes something to create such a thing and then build it up. And a poor concept or business model or delivery or depletion of funding or dozens of other things, or just plain bad timing, could bring it down. Remember MySpace?
The power of Facebook is in its popularity, and its popularity is in its power. Anything new that comes along has to compete with that. There might be 200 or 200,000 systems out there that are already trying to do that, and it could be another ten years before you hear of it.
The other day I asked my son to go call my husband to supper (that is, let him know the meal was ready). My son stood in the kitchen and yelled, “Dad, supper’s ready.” Then he turned to me and said, “Wireless communication.” There’s always that.