Peter Akkies is a productivity educator focused on the practical craft of personal task management — particularly the use of Things 3 (the popular Apple-platform GTD application) as a deliberate productivity system.
His CourseFlix listing carries Organize Your Life with Things 3 — a structured walkthrough of Things 3 as a GTD-style task-management system, covering the inbox / project / area structure, the planning workflows, and the patterns for making Things 3 a real productivity tool.
Material is paid and aimed at Apple-platform users (Mac, iPhone, iPad) ready to take task management as a deliberate practice. For broader content, see CourseFlix's Developer Productivity category page.