Twilio's Two-Factor Authentication is the fastest way to add a second factor of authentication to your web application. Tacking something you have to the something you know of a password provides a huge step up in security while minimizing the disruption for your users.
Here we've collected Two-Factor Authentication quickstarts in various web programming languages. In each, we'll guide you down the fastest path to two-factor while incorporating security and programming language best practices.
Our web programming language quickstarts build out our example application which incorporates Two-Factor Authentication across four channels: SMS, Voice, Soft Token, and Push Notification. Note that Soft Token and Push Notification demos will require you install the Authy Client.
Our Authentication SDK allows you to easily build your own two-factor authentication client for iOS or Android. It facilitates easily adding time based one-time-password (TOTP) or Push Notification support in your own mobile app.
These quickstarts no longer reflect all of our suggested best two-factor practices but are still useful demonstrations of a two-factor implementation. They are kept here for posterity - please use the quickstarts above first.
Got Two-Factor properly protecting your quickstart app? If you followed the Two-Factor Authentication quickstart, the app also added features for Phone Verification. If you haven't yet, try the Phone Verification quickstart next.
We've also got a large collection of Guides and Tutorials with example Two-Factor Authentication applications along with code for other Twilio Communication and Account Security products. You can find a detailed description of all of the concepts and code in our Two-Factor Authentication API Reference.