I was thinking about tagteam (ao3/Tumblr) and it led me to think about other apps and their relationships so have my headcanons (which also includes other siteships I've seen/heard of)
Ao3 and Tumblr kissed at a lake after running out of the hospital and that's how they went from friends to dating/married immediately. They both couldn't stand going through more slow burn.
Twitblr breakup was horrific and bloody and that's all I'll say.
Twitter and Bluesky dated but in the "ha! Look at me I've totally moved on!" way on Twitter's half (Bluesky had a massive like crush like one would have on a celeb on Twitter that's why it lasted a lot longer than it should've. Bluesky is currently single and happy.)
Ao3 and Wattpad are siblings and Fanfiction.net is their parent. Fanfiction.net also had something with Wikipedia but neither talk about it anymore. They are still on good terms though.
Wattpad and Webtoons are soft dating. Not really dating but they dunno how else to label themselves.
Vine and TikTok are cousins who fucking HATEEEEE each other. They tolerate each other only when YouTube is around (shared enemy)
Pinterest and Spotify are dating, and are very into public affection.
Spotify, SoundCloud and Apple Music used to be a polycule but they broke up and are all bitter ex's but somehow that effects nothing. Mutually bitter and mutually fine with it.
Pinterest and Tumblr are penpals who exchange notes. Pinterest sends fashion and pretty designs while Tumblr sends their best shitposts and poems.
Netflix, Hulu and Disney+ are work colleagues (all streaming apps work together) and they share gossip. This not change the fact that they HATE each others guts but hey at least its better than hanging with Amazon Prime Video.
Opera and Discord have a massive on and off relationship. They hook up at least once a week.
Roblox and Wattpad are best friends. No explanation I just think they would be besties.
Google Docs and Notes (or is it called Apple notes? Who knows) are dating and ao3 works at the library they own.
Google and Wikipedia also used to date.
Fandom is Wikipedia's kid.
All of them are gender fluid. Go wild.

















