What are third-party Reddit clients and why are they controversial?

Third-party Reddit clients are mobile or desktop applications built by independent developers that use Reddit's application programming interface (API) to deliver the Reddit browsing and posting experience through a custom interface, rather than through Reddit's own official app or website. For many years, clients like Apollo (iOS), Reddit Is Fun (Android), Relay, Sync, Narwhal, and others were considered superior to Reddit's official app by a significant portion of the platform's most engaged users, offering cleaner interfaces, better customization, faster performance, and more powerful features. The controversy around third-party clients escalated dramatically in April 2023 when Reddit announced it would begin charging for API access that had previously been free. The pricing announced was extremely high relative to what any third-party client could afford through subscription revenue: Apollo developer Christian Selig estimated he would owe Reddit approximately $20 million per year under the new pricing structure. This announcement triggered a major community protest in June 2023 in which thousands of subreddit moderators made their communities private or restricted for several days. Reddit's CEO Steve Huffman stood firm, and the new pricing took effect on June 30, 2023. Apollo, Reddit Is Fun, Sync, and BaconReader shut down on that date. A few clients like Narwhal and Relay pivoted to paid subscription models to survive. Reddit stated that its motivation was commercial fairness — it no longer wanted to subsidize the server costs of applications profiting from Reddit's content — though critics noted that the timing coincided with Reddit's need to demonstrate data control ahead of its 2024 IPO and its data licensing negotiations with AI companies. Some accessibility-focused apps received exemptions from the pricing changes.