Duo Security - Duo Security provides cloud-based two-factor authentication. Duo’s technology can be deployed to protect users, data, and applications from breaches, credential theft, and account takeover.

Google Authenticator - Google Authenticator is a multifactor app for mobile devices.

Microsoft Authenticator - One app to quickly and securely verify your identity online, for all of your accounts.

Authy - Best rated Two-Factor Authentication smartphone app for consumers, simplest 2fa Rest API for developers and a strong authentication platform for the enterprise.

Rublon - Rublon enables your workforce to securely access your organization's networks, servers and applications via easy-to-use multi-factor authentication. Protect cloud apps, VPNs, servers, workstations, internal as well as on-premise apps.

Lastpass - LastPass is an online password manager and form filler that makes web browsing easier and more secure.