2FA
2FA is short for "2 factor authentication", which for me, is based on these.
- Special hardware (eg ETrade)
- Twilio Authy (In addition to devices it runs on desktops too, including Linux)
- Google Authenticator
- SMS
Listed in order of personal preference. There are others. SMS is the least secure, avoid this one.
I want to try one of the commercial widgets, um, brand? but don't want to pony up the $45 per token. (= $90 because 1 for me one for backup) The idea here is that you plug the widget in as a USB device and then as long as it's plugged in you don't need to type the 2FA code.
Migrating to > 1 device
I want redundancy and currently I have just one Android phone set up.
Twilio Authy -- add more devices whenever it's convenient. Use a phone or a desktop. https://www.techrepublic.com/article/how-to-set-up-authy-on-multiple-devices-for-more-convenient-two-factor-authentication/
Google Authenticator -- cancel service at each provider, then add back in and set up all devices. Not convenient. I will migrate everything to Authy that is supported. https://medium.com/@jackknutson333/setting-up-google-authenticator-on-multiple-devices-1a09c4094e02
Authy guidelines
https://authy.com/blog/understanding-2fa-the-authy-app-and-sms/