Trakt.tv is a very helpful little plugin for Kodi. What makes it so helpful is that it acts as a backup of what I’ve watched and how far through a series I am. After every movie or TV program it asks me to rate the show (optional). More importantly it records that I’ve watched it by “scrobbling” (just sending what I watched and when) up to the Trakt.tv portal and records it on my profile.
I’m sure it collects my viewing habits and does some strategic selling of my statistics somewhere along the line. But fair play to them. If I wanted to I could join in with the whole social aspect of discussing what I’ve watched, but what I get out of it happens when I reinstall Kodi. I activate the plug-in, it then syncs with my profile and marks all the local media I’ve actually watched as watched.
So I always know where I’m at.