If you're looking for something other than OTPless, Clerk is another good option. It's a full-stack user management platform that handles authentication and user management with features like multifactor authentication, passwordless authentication, magic links and email/SMS one-time passcodes. Clerk also supports a variety of frameworks and offers multi-tenancy support, so it can work with a variety of user needs.
Another good option is PropelAuth, a multi-tenant authentication service that supports a variety of sign-in options, including passwordless magic links and 2FA. It also offers customizable roles and permissions, advanced security features and support for frontend and backend libraries. PropelAuth is geared for B2B products and has a clear pricing model.
If you're looking for something that focuses specifically on passwordless authentication, you might want to check out MojoAuth. The service offers a secure and frictionless login experience for web and mobile apps, eliminating the security risks of passwords. MojoAuth supports a variety of industries and offers easy-to-use APIs for developers, so it's a good option for those looking to improve user experience and security.
Last, LoginRadius offers a user identity management platform that includes support for advanced login options like social login, phone login and passwordless login. It offers a cloud-based directory service for customer insights, data governance for regulatory compliance and secure user profiles. LoginRadius is designed to scale and handle high volumes of login requests, so it's good for companies that need a more powerful identity management system.