I am on a Nexus 5x running 7.1.1. Earlier today found no cards on the Google Now screen, just this message: "New Version Available A more recent version of the Google app is available for download". So tapped the link which took me to the Play Store and the Google App. Where there is no update available, just options to open or uninstall.
Hitting open loops me right back to the above message.
Fixes I have tried: Turning Now off and back on. Deleting card preferences. Uninstalling Google and the Now Launcher and reinstalling both. Turning location services off. Have also checked that Settings>account & privacy>Google activity controls>web & App activity is set to "On". Oh, and switching my phone off and on again :-) None worked. Any help would be greatly appreciated.