Helio

Helio is an open‑source music sequencer that runs on desktop and mobile devices. It offers a lightweight, distraction‑free interface designed to let composers focus on their ideas without excessive visual clutter. The software visualizes musical material in a straightforward manner and includes documentation on hotkeys, refactoring tools, and microtonal temperaments to support learning and experimentation.

The sequencer supports a range of plugin formats, including VST, VST3, LV2, AudioUnit, and SoundFonts, and can operate with various audio back‑ends such as CoreAudio, ASIO, DirectSound, ALSA, JACK, and OpenSLES. Users can export projects to MIDI, WAV, and FLAC files, facilitating integration with other audio workflows.

Targeted at composers and musicians who prefer a clear, minimalistic workflow, Helio aims to provide a cross‑platform solution that balances functionality with simplicity, while remaining stable and actively maintained.