Martchus / tageditor

A tag editor with Qt GUI and command-line interface supporting MP4/M4A/AAC (iTunes), ID3, Vorbis, Opus, FLAC and Matroska

GPSBabel / gpsbabel

GPSBabel: convert, manipulate, and transfer data from GPS programs or GPS receivers. Open Source and supported on MacOS, Windows, Linux, and more. Pointy clicky GUI or a command line version...