I have a couple of apps that say they have the ability to sync to my calendar and when I turn it on my calendar shows up I hit sync but the event doesn't show up.
It's not an option to control the sync in either app.It's possible that the sync is not instant, and could be defaulted to update in intervals. Is there an option/setting in the apps that control the sync?
Make sure you go into settings, privacy, then calendars and make sure you are allowing access.