#Trello alternatives. I've found [#TimecampPlanner](https://planner.timecamp.com), which is rather more like a fully-developed PM tool.
* It seems cheap-ish, less than USD4 pm per seat.
* It integrates with external calendars cleanly and well, using ICS links.
* Trello board -> Timecamp Planner project.
* The 'main app' is Timecamp itself, which seems to be a way for freelancers to track time. I don't need that right now, but it looks interesting.