The Narwhal developer previously requested that Reddit let him use the API for free, if he agreed to make no money from the app. Seems like that happened. https://9to5mac.com/2023/06/29/narwhal-reddit-deal-third-party-app/
As Apollo and other apps close down, Narwhal seemingly agrees to one-off deal with Reddit to stay in business

The public deadline for the Reddit API changes is July 1. Popular third-party client Apollo is one of the casualties,...

9to5Mac
@bzamayo I’ve used Apollo ever since I was on Reddit. With the advent of all this nonsense, I’m done with Reddit - good riddance.