1. Overview In this article, we will demonstrate how to record a voice to enable 2FA using voice biometrics. To use Voice Biometrics, it is necessary WebADM 2.0.* and OpenOTP mobile application version 1.4.11 or higher for Android and version 1.4.13 or higher for iOS. 2. Voice Biometric Registration In order to record a voice biometric to a user, log in on the WebADM admin GUI, in the left LDAP tree, click on the user account that you want to register a voice.