Excellent. I actually like Apple's practice in this regard: they have a barebones/baseline functionality but allow third parties to provide a value added replacement that can be a first class replacement.*
Apple is almost there with mail, addressbook, and calendar but perhaps surprisingly they aren't as seamless as it is with passwords.
* For example this allowed me to plug 1password into my parents' phones and computers and use the shared vaults to make sure I could help them get unstuck from various web sites. Plus when they pass on I'll still be able to help the surviving parent to get access to things they need from the other parent's device. The apple one is disabled so they can't even accidentally get something confusingly stored in it.
Apple is almost there with mail, addressbook, and calendar but perhaps surprisingly they aren't as seamless as it is with passwords.
* For example this allowed me to plug 1password into my parents' phones and computers and use the shared vaults to make sure I could help them get unstuck from various web sites. Plus when they pass on I'll still be able to help the surviving parent to get access to things they need from the other parent's device. The apple one is disabled so they can't even accidentally get something confusingly stored in it.