Mine is originally using Baconreader while in the dorm community bathroom doing a deuce and seeing a mention of Sync. Installed and instantly became a user. Later on I had a problem with the app because I was running beta Android. Reached out to the dev and after a few fix attempts an update was posted that fixed the issue. To get that kind of support is rare and is why I have continued to stand by Sync all these years.
I switched from ios to android 3 years ago. I searched for apollo replacements and sync popuped up. One thing I found intersting with sync is it was the only 3rd party app (aside from apollo) that had push notifications.