I made a simple timetracking webxdc app, it meant to be used by one user. Later there could be a fork of this app or a build flavor that supports multiple concurent users.
You can send it to youself in the saved messages and timetrack across multiple devices, if you use different accounts on your devices, you could make a group and use it there on all your devices.
It’s timetracking on multiple devices, but without the need for a cloud.
The app is still work-in-progress, the design still needs love and there are many features I still want to add to it. Your Feedback is welcome!