Passwords are weak and often cracked. Two-factor authentication, which uses your phone number to send a secondary code you have to enter, is much stronger.
I know first-hand how scary password hacks can be, but I still put off two-factor authentication for years — relying instead on a strong multi-digit 1Password-generated password — because it felt clunky and hard to set up. What if I lost access to my phone number because I was restoring my iPhone? What if I couldn't get network access for my two-factor code? Too much hassle, I thought.
Authy changed my opinion on two-factor authentication: The app makes it far less terrifying to deal with; it also lives on both my Mac and iOS devices, so I don't have to worry about losing access to my accounts while my phone is restoring.