Fixing Google Calendar and Gmail in iOS 7

My Google calendars disappeared while comparing Fantastical 2 with the built–in Calendar app (iOS 7.0.3, iPhone 4S). I mentioned this before, and somehow “fixed” it:

I think I deleted and re–added the account, and all was well. Temporarily.

After some searching, here are a couple articles that explain why I was tripping:

  1. How to enable push Gmail on your iOS device“. You add an Exchange account for push e–mail. I originally set this up while using iOS 5, and probably followed the same steps over a month ago. Not sure why that continued to work until now.
  2. A new way to sync Google Contacts“. I was overdue in adding a separate CardDAV account, but was apparently built into adding a Google account process in iOS 7. Also not sure how that worked while I was on iOS 6.

How I fixed things:

  1. In Settings, then Mail, Contacts, and Calendar, delete my Google account (previously configured as Exchange).
  2. Follow the instructions from the support page, “Sync Google Calendar with your iOS device“. The notable difference is adding a Google account, not Microsoft Exchange. You can also turn on Mail or Contacts without configuring a separate IMAP account or CardDAV account, respectively.