I use Anilist. It has a nice clean and user friendly interface. The progressive web app also works well on my device.
I use both Anime-Planet and MAL.
I joined Anime-Planet one time MAL had an outage, I think. Both sites have their advantages. A-P has a very rich database of tags, for both anime and characters, and also has a personal feed history that stretches back way longer than MAL’s does. On the other hand, MAL includes metadata fields for when I started/finished watching something, and has some third-party sites that integrate with it, such as anime.plus, which I use to see stats on how much I’ve watched and when and how I’ve rated things.
So, for now, I just use both at the same time.
I once tried Kitsu, back when it was called Hummingbird, but I wasn’t very satisfied with it. Haven’t ever tried AniList or AniDB.
Neither, AniDB.
Set up is a pain though, terrible defaults.
Anilist is pretty good, I left MAL a few years ago and never looked back.
I use AniList, Anime-Planet, LiveChart, AniDB, and MyAnimeList
Reasons I use each:
AniList gives good stats and breakdowns of what genres, etc, you tend to prefer in a clean, user friendly format
Anime-Planet gives me generally good recommendations, based on anime I want to see something like, or my overall library preferences
LiveChart's just good at giving me what I'm looking forward to in a good digestible feed. Sometimes I scroll through past seasons to see what I may have missed, this is why I maintain a list there
AniDB gives incredibly detailed analytics, has a cool timeline of all your anime watching history. I think this is just really satisfying to look at
MyAnimeList honestly doesn’t really have much I care about, just people tend to get squirmish if I link them anything else, so it’s the easiest list to send to people without having to explain why I don’t use MAL
I use both, if MAL is down there is always Anilist to keep my episodes tracked.