Hello,
I was a XBMC user and used all the time a feature that could change subtitles offsets to make it sync correctly with audio. That was very helpful instead of looking for srt files matching exactly the audio for hours. I just had to get a good srt file from within my movie and decrase or increase 1 second for example. One minute lost of my life, at most …
When I started with plex on Android, I didn’t see any feature like that BUT I heard it was implemented on PHT so I imagined the feature would be there soon enough on Android/iOS apps too.
So I bought a plex pass and chose to wait and deal painfully with my subtitles on plex apps a few month again before it was released.
WRONG ! After so much time, it didn’t seem to get released so I’m asking kindly instead of just waiting 
Think about the offline syncing. We love to sync unseen content to go on holidays. What happens when you open your movie or TV show episode for the first time and you can’t see it because of a 1s delay ? And you can’t download another subtitle file before returning home, that’s kind of irritable, isn’t it ?
Could you add this killing feature to deal correctly with subtitles on any app ? Even web app if you want too 
I will love you forever 
Thanks !