I've been using Basecamp with a project I was contributing to. I really liked the so called "Camp Fire" which is a global chat to leave messages that everyone can see.
You can then create boards and add items to boards and add a ToDo list, documents, images to each item, comments if you have anything to say and assign each item to anyone. Not only admins but anyone can assign people to any item so if you are working with an artist you can just assign tasks to the artist and give it a deadline when do you expect it, send a notification even, have a chat about each item in comment section if there is any question. Also no performance issues and have an awesome mobile app. Pretty nice.
However, we were using the paid version, I didn't try the free version, don't know what limitations are there.
For my personal projects, since I am working alone in private, I usually just use a ToDo app or a notes stored in the cloud and that's it
On Trello I believe you can also add somehow a ToDo list to cards so you can make it like
Game board
-Title Screen card
[x]play button
[x]options button
Maybe it is one way to go about it.