Auto-sync is controlled by iOS, and your phone will automatically perform background tasks such as auto-sync when it thinks it's a good time. Please be aware that if your screen is off/locked, it will stop or prevent auto-sync. Apple needs to learn your phones usage so it can know the appropriate time to perform background tasks. Auto sync might take a couple days to work as iOS makes these calculations. Here are a couple things to check to make sure it will work:
- Is location service enabled for our app?
- Is background fetching enabled for our app?
- Are you leaving the app running in the background?