Duets.fm is an unofficial companion app designed for Smule singers. The app offers various ways to enjoy your songs, including playing a random mix of unrepeated songs from your collection, marking favorite singers to play only their joins, and creating easy-to-use playlists.

Moreover, Duets.fm enables users to search for songs based on date range, singer, or song type, providing insightful stats such as the number of songs you've joined with each singer and vice versa. Additionally, users can identify singers they follow but who are not following them back.

Furthermore, the app allows users to download songs for offline listening, seamlessly navigate from songs to singers' pages on Smule, and access contextual help by long-pressing anywhere within the app.