I think I've heard of them once, but what does Twilio bring to the table to enrich Authy? Plus, Authy is literally competing against Google Authenticator, which despite the name is open source and free to use. Authy is asking nearly 10 cents per auth: https://www.twilio.com/two-factor-authentication/pricing
The funny thing is that as and end user, I can use authy to replace my Google authenticator, since it also implements the same protocol. So I use it for all my 2fa codes, mainly so I can access it from places other than my phone if needs be. I wonder if authy has monetized my use case somehow (adverts most likely).
The price per auth was incredible when I priced it out once. It was going to be several hundred K per year just to support normal 2FA with it.
The other thing they advertise us 2FA for actions. So not just on login, but on actions. Imagine getting a 2F push notification that someone is transferring 5k out of your bank account, accept?
That also means the price isn't just logins, but could also be sensitive actions!
Just FYI, Google Authenticator is no longer open source. The last open source version was released 5 years ago.[0] TOTP is an open standard though, and can be implemented by anyone, such as Authy has done.
Other way around, Authy gets Twilio another channel to upsell telco services. $0.09/auth is fine if you cache it for 30 days/ever.
And why not Google Authenticator? Some people either want to avoid Google products or be more appealing to customers who want to avoid Google. I know of Authy since itch.io use them.
Authy replicates data so you can have your 2FA on multiple devices and easily restore them if your phone dies.