Hm. Mirakel 3.0 apparently doesn’t work, but 2.8.2 is still on F-Droid. Compared to the "Taskwarrior" app there, it seems much more polished, with the Taskwarrior app, I have a hard time figuring out how to e.g. add subtasks to a problem (or even hide existing subtasks from cluttering everything). Do you have an even better alternative?