Are passkeys sharable across platforms? Can shared passes be revoked? And what is the mechanism for resetting a passkey?
Sharing Passes across platforms?
Using AirDrop is currently the only way for different users to share the same passkey. However, services should support having multiple accounts for the same account. For sharing accounts with passkeys across platforms, it's generally recommended to do a nearby device sign in the first time (which signs you in without sharing the passkey), then create an additional passkey on the other platform once signed in.
For revocation and resetting, we've just added a new section to the Supporting passkeys developer documentation explaining how that works.