Third-party apps were first. Reddit bought Alien Blue in 2016 IIRC, a reasonably mature third-party app, to turn it into their official app and promote it very aggressively in mobile browsers.
yes, and they did a horrible job of that. And instead of listening to feedback to improve the app (some improvements of which mods rely on to do their free labor) they aquired and then butchered, they reduce choices.
