Here is how you sync your iphone yahoo calendars!
Go to this link agree terms to share your yahoo calendar.
switch.calendar.yahoo.com
great now go to iphone setting icon and select. Then choose mail, contacts, calendars and then add account. Next choose "Other" and then choose add CalDAV account. For server use caldav.calendar.yahoo.com and the use your yahoo user name and password! Your calendar will now show up on your iphone.
Go to this link agree terms to share your yahoo calendar.
switch.calendar.yahoo.com
great now go to iphone setting icon and select. Then choose mail, contacts, calendars and then add account. Next choose "Other" and then choose add CalDAV account. For server use caldav.calendar.yahoo.com and the use your yahoo user name and password! Your calendar will now show up on your iphone.