Could someone please clear up my confusion as I am not very familiar with email protocols and standards. Which of the following will not work after Jan. 30th?

iOS - CardDav for contacts (2 way sync) - Exchange for email and calendar

Android - default setup, I added my gmail at setup - email, contacts, tasks, calendar... all work out of the box once you have added your gmail account.

Thunderbird (PC) - email, contacts, calendar