PayPal says the rollout will start on its website, rather than its app, and that you need to be running Chrome on Android 9 or higher to access the passkeys. If it is available for your account, you may receive a message asking if you want to create a passkey, which you can authenticate using biometrics or the passcode you use to unlock your phone.
Access keys are based on FIDO authentication standards and are generally compatible across platforms, although as PayPal shows, you may have to wait for a site or service to implement support on each platform you use. Several password managers, including those built into iOS and Android, support syncing passkeys between devices, and there are ways to access them when you’re using a device they’re not synced with as well.
Despite several big tech companies pitching passkeys as the (no pun intended) key to the passwordless future, they are still relatively rare. 1Password has a page that keeps track of the sites and services that support them, and while it has some big names like Best Buy, Okta, Microsoft, and eBay, there are still only 38 entries on the list. Even if there are actually twice as many sites that support passwords, it would still be pretty hard to get rid of passwords at this point.