Google is a big proponent for 2-Step Verification, and is today improving the experience on iPhones. You can now sign-in to a Google Account on iOS using USB/NFC security keys.
Google’s login page in apps and the web is adding native support for the W3C WebAuthn standard on iPhones and iPads running iOS 13.3 (released in December) or later. This allows you to use USB/NFC security keys instead of just Bluetooth and phone-based keys, which require installing a separate Google Smart Lock app.
For example, users will be able to just tap an NFC security key to the back of an iPhone when prompted after entering their username and password. USB-C models can also be plugged in directly on compatible iPad Pro devices, while you can use Lightning to USB adapters for keys that were previously only used with desktops/laptops.
Google notes a collaboration between Apple, the FIDO Alliance, and the W3C for making this possible. Security keys are touted by the company as the “strongest form of 2-Step Verification” and are required for the Advanced Protection Program.
This is available for all G Suite and Cloud Identity customers, as well as personal Google Accounts. iOS support for USB/NFC security keys is gradually rolling out today and will be available over the next two weeks. Set-up instructions are available here.