Manage a plain-text to-do list from the command line.
Free and open source (GPL-3.0 licence per GitHub).

Notes, tasks & docs
Keep simple task lists and subtasks on your Linux desktop.
Keep simple task lists and subtasks on your Linux desktop.
Everyday personal lists, task notes and subtasks on Linux. Not advanced automation, Apple ecosystem sync or full Todoist team functionality.
Simple lists rather than full project management. Linux Flatpak is the supported distribution. No native Apple apps, Todoist collaboration or equivalent natural-language scheduling. Nextcloud is the documented working sync route; other CalDAV providers may fail and hosting can cost money.
Each comparison covers the workflow described above, rather than every paid feature.