I have the Fenix 3 HR that I use with Android. My girl friend has a Forerunner 235 with iOS. Her watch does not sync when we do an activity and come back in range of our phones. Mine watch will always auto sync my activity. She always has to open the Garmin Connect app and wait for the sync process to start. She does have background refresh on, but that doesn't help. Do Garmin watches not auto sync activities and steps on iOS? Is this a limitation of the Forerunner 235?
Her notifications work just fine as long as the app is left running in the background. This feels like an iOS thing to me. For example, Google Photos will not upload pictures in the background. The app has to be open for it to sync.