The list of third-party apps that support passkey login on the iPhone has grown by one, thanks to TikTok. Users of the popular video-sharing service will now have the option to sign in with their passkey associated with their Apple ID, which means they can easily get into their account using Face or Touch ID. Passkeys are considered a safer option than password logins, since they're comprised of a cryptographic key pair.
One of the keys is a public key that's associated with the website or service, while the other is a private key stored only in the user's device. Services and apps like TikTok don't have access to that private key, and users can't copy it down or give it out, making passkeys resistant to data breaches and social engineering by bad actors. iOS devices authenticate users' identity for logins using their biometric data before matching their private key with a service's public one.