Here in Iceland, there's a security key embedded in your SIM card that everybody uses as their 2FA solution. It's triggered via a GSM message to your phone, id

Here in Iceland, there's a security key embedded in your SIM card that everybody uses as their 2FA solution. It's triggered via a GSM message to your phone, identifies what the authorization is for, and lets you enter the key's PIN code to accept. The whole thing (except the UI) is isolated from the phone's OS so that even if your phone gets lost or compromised nobody else can auth as you.