Gluu Server vs. Auth0
Gluu Server
gluu.org/Gluu offers various authentication solutions based on open-source software. There is a self-hosted solution, a managed solution, and a free fully open-source solution based on the Linux Foundation Janssen Project.
Auth0
auth0.com/Auth0 is a flexible, drop-in solution to add authentication and authorization services to your applications. Your team and organization can avoid the cost, time, and risk that come with building your own solution to authenticate and authorize users.