RuneAudio is described as 'free and open source software with one specific objective: to transform an embedded platform (a cheap, silent and low-consumption mini-PC) into an Hi-Fi digital music player' and is an app in the Audio & Music category. There are four alternatives to RuneAudio for a variety of platforms, including Linux, Raspberry Pi, Self-Hosted solutions, Android and iPhone. The best alternative is Volumio, which is both free and Open Source. Other great apps like RuneAudio are moOde audio player (Free, Open Source), Pi MusicBox (Free, Open Source) and Balena Sound (Free, Open Source).
Volumio is a free and Open Source Linux Distribution, designed and fine-tuned exclusively for music playback. It runs on a variety of devices, typically small and cheap computers like the Raspberry PI, but also on low power PCs, notebooks or thin clients.
moOde audio player Moode Audio Player is a derivative of the wonderful WebUI audio player client for MPD originally designed and coded by Andrea Coiutti and Simone De Gregori, and subsequently enhanced by early efforts from the RaspyFi/Volumio projects.