How do I force iOS Reminders to sync? Reminders on iOS is often out of sync with Reminders on my other devices and iCloud. How do I force it to sync?
Opening up the calendar and allowing it (or forcing) to sync will do the trick, though oftentimes imperfectly.

To force calendar to sync, open it up and the tap "Calendars" at the bottom, then swipe down.

As far as "imperfectly" goes, I mean it doesn't seem to sync all tasks all the time. I haven't figured out what the pattern is there, but it seems that it's usually recurring tasks that have issues.