Apps similar to Duo mobile include Aegis Authenticator, which is free and open source. Other options are Proton Authenticator, 2FA Authenticator (2FAS), Authy and Stratum. Authenticators like Duo mobile are a crowded field, with more than 50 alternatives for iPhone, Android, iPad, Mac and Linux.
Keysmith is a token generator for your two-factor authentication (2FA) logins. It supports time and hash-based one-time passwords (TOTP/HOTP).
Germany
EU
OTP authenticator app for managing your 2FA / OTP codes on iPhone, iPad, Mac and Apple Watch.
Australia
Gnome Authenticator is a desktop 2FA code generator for Linux desktops, like Ubuntu.
CzechiaEU
An awesome two-factor authenticator based on Flutter, supports Android, Windows and Linux platforms, and supports multiple cloud backup methods such as Onedrive, Dropbox, WebDAV, S3Cloud, etc.
China
LastPass Authenticator offers a unique one-tap password verification experience that no other authenticator app delivers.
United States
Protectimus Solutions provides a powerful multi-factor authentication service. We offer 2FA SaaS platform and on-premise version of the product which supports a great variety of TOTP tokens and program tokens for OTP delivery.
United Kingdom
Encrypted Windows app for managing 2FA codes with AEGIS-256 and Argon2id, supporting Windows Hello, portable use, multilingual interface, token import/export, QR code/manual entry, generic TOTP, local storage, and dark mode interface for enhanced security.
GermanyEU
Fob is a 2FA authenticator built for people whose account list outgrew a flat scroll. Every account can carry multiple tags (work, finance, crypto, a side project) and you filter by any combination of them, not one rigid folder.
United States
GTK+ application for securely managing TOTP & HOTP tokens. Content is encrypted on disk using AES256-GCM. Master password derived using PBKDF2 with 100k iterations & SHA512 as hash algorithm. Can import encrypted backups from andOTP & Authenticator+.
ItalyEU
Open-source Android authenticator supporting TOTP and HOTP, material design UI, backup and restore via files, Google Drive, or Android backup, works offline, privacy-focused, no analytics or ads, suitable for securing logins on popular services.
Etopa is a two-factor-authentication app, which runs as a web server and can be accessed using a web browser or using an Android app. You can use the Etopa.de instance or host your own.
Allthenticator unifies digital and physical access with one smartphone-based identity. Users log in to systems and unlock doors via proximity. Supports SSH keys, passkeys, OTP, and peer-based recovery—all managed from a single admin dashboard.
United States
