You can now use a physical security key to log into Facebook on Android and iOS
Facebook has just announced an improvement in its security features by making hardware security keys compatible with two-factor authentication across iOS and Android devices.
Since 2017, hardware security keys on Facebook accounts have only been available for desktops as an authentication method in their own right, without being able to be used alongside another method in two-factor authentication.
As of today, however, security keys will be available to to mobile users across the world, allowing anyone to set up two-factor authentication and log into Facebook on iOS and Android mobile devices using a security key.
In case you aren't sure what factor-authentication is, it's a security feature which requires proof by asking for something only you know (your password) and something you have (such as a text to your phone).
Hardware (physical) security keys for mobile accounts are usually small drives which are easy to carry around, and which notify you every time there's an attempt to access your account from an unrecognized device. By using a physical security key along with a password, for example, the chances are nearly nil that any hacker could get ahold of both and enter your account.
Facebook suggests public figures or celebrities might stand to benefit most from incorporating a physical security key into their accounts, as they are at a greater risk of being hacked—although anyone who could be bothered to use such a key would benefit from essentially guaranteed account safety.
Although Facebook doesn't sell hardware keys, you can always purchase them from a third-party hardware store such as Micro Center. The keys can work both through Bluetooth and by directly connecting it into your phone's charging port.
Yubico 5 NFC Security Key, available in Micro Center
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