Google Titan - A 2FA device to protect yourself from hackers
Cotter - One-click phone number login and checkout
Rapid 2FA - A painless way to add two-factor authentication to your site
Authorizer - Authorizer is an open-source authentication and authorization solution for your applications.
Clerk SMS for Slack - Send and receive SMS directly in Slack with your team members.
Authenticator App by 2Stable - An extra step of security never hurt anybody. Enable two-factor authentication on your online accounts and let Authenticator App by 2Stable do the rest.