The interface matters a lot. I am using https://timeular.com/ (along with their neat physical tracker widget) and it has become the tracker interface to beat, as the UX is really solid. I use it every day and find it extremely productive in ensuring that I spent time coding/learning etc instead of too many meetings or other activities that can hijack your day.

Having said that, this is a good effort. I really like the continuing trend of useful software coming via Open Source, via a vibrant tech community.