Authy vs Duo Mobile

Authy is a free two-factor authentication app for Android and iOS that generates TOTP codes for online accounts. Users can scan QR codes from services including Facebook, Amazon, Google, Microsoft and Dropbox, then access tokens on a phone, tablet or Apple Watch. Codes are generated on the device, so a phone does not need an internet connection to access secured websites. Authy supports encrypted backups and synchronization across multiple devices. Access to tokens can be protected with Touch ID, a PIN or a password. New devices can be added through SMS, voice or approval from an existing device; users can also rename or remove lost or stolen devices and disable future app installations. Authy says it encrypts authentication data and cloud backups without retaining users’ backup passwords. That means a forgotten backup password cannot be recovered through Authy. Its listed free plan costs nothing and includes two-factor authentication, encrypted cloud backup and multi-device support.

Duo Mobile provides two-factor and multi-factor authentication for company and personal data on iOS and Android phones and tablets. Users can approve or deny sign-ins with Duo Push, or enter time-based passcodes generated by the app. It also supports third-party TOTP accounts, biometrics, and passcodes. Duo Restore backs up and restores Duo-protected accounts when a user changes devices, and Security Checkup provides a mobile-device security score through app notifications. For organizations, Duo connects with legacy infrastructure, custom apps, VPNs, SaaS tools, and offline devices. Integration methods include RADIUS, SAML/OIDC, Duo Authentication Proxy, and direct API connections. Adaptive policies can consider user role, location, application, network, and device health. Duo says it keeps private keys on users’ devices in a tamper-proof secure element and does not store passwords. The free plan covers 10 users; paid plans start at $3.00 per month, and a 30-day trial is listed. End users needing enrollment or troubleshooting help are directed to their organization’s Duo administrator.