Generate One-Time Passwords (OTPs) using a YubiKey NEO hardware, connected using NFC. It generates codes that are compatible with Google two-step verification, and can be used with any other site that supports OATH TOTP. There are two apps for YubiKey NEO and OATH: YubiTOTP and YubiOATH. They work differently, and both are supported, but to get the most features and best user experience we recommend use of YubiOATH. The YubiTOTP app works with all YubiKey NEOs, however it is more limited than the YubiOATH app. The YubiOATH app requires that the (free software) ykneo-oath applet has been loaded on to the YubiKey NEO. The YubiTOTP app is still maintained for backwards compatibility.