Auth0 is a cloud service that provides a set of unified APIs and tools that instantly enables single sign-on and user management for any application, API or IoT device. It's modern identity infrastructure, built for developers. Auth0 provides open source SDKs for all popular platforms, all popular operating systems, all popular devices and all popular programming languages. It allows connections to any identity provider from social to enterprise to custom username/password databases. Auth0 is obsessed with making identity, authentication and authorization simpler for modern applications.
FusionAuth is a single-tenant CIAM solution that deploys on-premises, in your private cloud, or on their fully-managed FusionAuth Cloud. Their JSON REST API provides advanced identity management that is easy for developers to deploy and implement on any platform or framework.
Stytch's APIs make it simple to seamlessly onboard, authenticate, and engage users. Improve security and user experience with passwordless authentication. Vendor downtime directly impacts your ability to engage users, which is why they’ve built failover logic across multiple vendors for SMS and email. Improve security and avoid account takeovers with passwordless authentication.