I too am trying to link ToDo with Siri on my iPhone 6 with IOS 11. I am following the instructions in this guide (http://support.appigo.com/support/solutions/articles/143954-creating-tasks-with-siri).
I get an error after trying to save the CalDAV settings headed "Calendar Account" with "CalDAV account verification failed". I have tried with SSL on and off and both don't work.
Please help! It must be a relatively simple solution.
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