Is there a Stephen Covey task manager?

Question

linux

Hello. There was a desire to streamline their affairs according to Covey. Before that, I used the Lightning extension for Mozilla ThunderBird for some time, but you can’t configure individual roles in it and divide tasks into four types by urgency and importance.
I use Fedora Linux and Android. The ideal solution would be a Linux application that would save everything to a file, and I would already synchronize via cloud storage. Also, as an option, an extension for Firefox or ThunderBird. Honestly, I couldn't find it myself.
If someone practices, tell us how you solved the issue with the tools, please.

Answer 1

Good online manager todoist.com/ , will it work?

Answer 2

There is also such an application - www.mylifeorganized.net/ - for PC, Android, iPhone, Blackberry, it's a pity I haven't seen a client under Linux yet...
I myself used MLO on PC and Android. It is synchronized via the cloud for $15 per year (if a student - there was a topic that you can send a scan of a studak and make a big discount)
Tasks are grouped into several levels of nesting, you can set any tags, reminders, export, view a list of completed tasks for the week ... At one time I was satisfied) Then, somehow imperceptibly, I rolled down to an ordinary notepad with a pen (there was little time to enter / hang tags).