Todoist

To-Do List app https://todoist.com/

created 2007, still active 2026

"Enhanced for Todoist 2.0": a free web app that gives you a new interface for your Todoist account, with features Todoist doesn't have, like an Eisenhower matrix or task durations. It's completely free, and your data is never sent anywhere except to your own Todoist account.

https://techcrunch.com/2012/08/02/task-manager-todoist-receives-a-major-html5-update/