Papership will still connect to a Zotero library and synchronize the items of metadata it has fields for. If the item has a URL and no attached file, Papership will (in my experience) reliably open the web location in its main window. If you do have a local copy but aren’t synchronizing files, this will create an error message. I can’t comment on its performance with file synchronization, since this is not something I do. A native Zotero iOS app is under development, but there is currently no release date.

An official Zotero ios app is being developed. Folks have had hit or miss success with Papership lately. It might work for you, so try it out. But don’t pay for any features until you are sure it’s going to work for you.