I use Letterboxd to manage my watchlist of movies. It's great because if I hear about a movie, I can add it to the watchlist, and if I'm looking for something to watch, I have a whole list! Even better, my partner uses the same app and it has a setting to show movies on both watchlists, which speeds things up a lot.
What do you use to manage your TV watchlist? Is there anything similar out there to what I'm describing, but for TV?