The platform let authors of socially useful or business ideas find mentors and experts who could participate in the process of ideas bootstrapping as co-founders. They are supported with all the tools they would get in case of registering a real legal entity. So they are able to issue shares, dilute them, conclude agreements, make collaborative decisions.
Simply saying, the platform to high level decisions and processes is what Github to source code and decisions on how it should be organized. Github let developers collaborate on programs' sources while CoLegion make it possible for co-founders to collaborate on start-ups during their early stages.