It doesn’t fit the bill perfectly but I’ve been using Obsidian with the Tasks and Day Planner plugins. Obsidian is no longer open source but I still like it because you have great control over your own data.

I use Syncthing to sync the notes between my phone and laptop (and select shared notes to the devices of my spouse).

The Day Planner plugins allows tasks to be time blocked / scheduled on a timeline of the day. There is also a week view and you can easily move from day to day.

You can sync your calendars so your calendar events automatically show on the timeline. Though I prefer to just check my calendar and enter the events manually.

The Tasks plugin lets you give tasks future or recurring due dates with some pretty flexible logic.

Aside from the day planning what I like the most is that I can also use this for journaling, to make project pages / dashboards, meeting minutes, and as a wiki. Take can live right with the appropriate information / context saving me from moving between multiple applications. I can save relevant attachments like emails in line with my notes and tasks just by dragging in the file (or directly dragging from an application like Outlook desktop).

In my opinion the sky is the limit with Obsidian. What I’ve described can feel a little rough around the edges but it works and the ability to build out your own process is unmatched. There are Kanban board plugins, drawing plugins (Excalidraw is amazing), and as for a mind map you can draw them or you can use built in view to see how all your notes link together.

I suggest watching some demo videos on Obsidian Day Planner plugin and Obsidian Tasks plugin, and Obsidian itself, and see what you think. You might be able to build out a system that works for you.

Well then use VLC and a remote control program like Unified Remote or KDE Connect and use your phone as a remote control for volume and mouse.

I second the recommendation of using Jellyfin.

Additionally you can use something like the Unified Remote app to make your phone control your computer instead of a mouse. Want to turn up the volume just use the volume rocker on your phone. You can also turn your phone screen into a large trackpad. Very convenient for watching media. I think there is an open source version called KDE Connect but I haven’t used it yet myself.

You realize this is the free and open source software community right? Replying to a call for development support with a commercial closed source product isn’t very helpful.

p.s. despite its “lack of developers” I’ve personally found Jellyfin to be superior to Plex with respect to its core functions.