Not everyone uses Apple devices.
Which are nowadays far more expensive and outperformed by competing products, only with the exception of iPad, the only “currently” performing tablet platform, hoping that iPad OS will provide what is still lacking from Apple iThings since the first iPhone: filesystem access.
Getting back to business…
Sync of tasklists and tasks are core business for Evernote, which lead Google to create Tasks and Keep, a mix of EverNote can do.
I agree that should be something standard for that, but currently on Android this feature is missing, provided by combined Calendar, Tasks, Keep.
Affordable tasks management applications which are WebDav-enabled are welcome