Relay was (yup) one of the third party apps that survived the API-calypse. But this sort of model is unsustainable in the long run, given that the competitor (the broken native app) is free and unlimited.
The obvious future monopoly of the broken native app is bad for the platform in the long run, given that Reddit always sucked off ideas from third party apps; and now there's no incentive whatsoever to make it better, after Reddit Inc. killed the better competitors.
It's one of the reasons I've moved over to lot of Foss apps over the years, and opting for using lite apps through the browser over downloading official apps.