Based on our record, Raivo OTP should be more popular than Open Authenticator. It has been mentiond 3 times since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
And about a free and open-source 2FA app, I think it's Raivo. I haven’t used it personally but I hear a lot about it. It's available on iOS and macOS, so you can check it out if it works for you. Source: about 2 years ago
It’s not Aegis but it’s open source and well regarded in privacy subreddits. https://github.com/raivo-otp/. Source: almost 3 years ago
I use personally use Ravio OTP which can send to the desktop using mac receiver once tapped in the mobile app, you also have better control over backups/exports. Source: almost 3 years ago
Google had a code hosting service (free for open source projects) with repo, issue tracker, and wiki. But it was shut down in 2016. Now there is just an archive: https://code.google.com/archive/. - Source: Hacker News / 10 months ago
Except Google will abandon it just like they abandoned https://code.google.com/archive/. Source: about 2 years ago
Aegis Authenticator - Aegis Authenticator is a free, secure and open source app to manage your 2-step verification tokens...
Authenticator - Authenticator is a simple, free, and open source two-factor authentication app.
andOTP - andOTP is a two-factor authentication App for Android 4.4+
OTP Auth - The app for calculating one-time-passwords on iPhone and iPad.
Google Authenticator - Google Authenticator is a multifactor app for mobile devices.
Tofu Authenticator - Tofu Authenticator is an open-source easy to use two-factor authentication app that lets you secure your accounts with one-time passwords.