The website is great for drawing surprisingly! It doesn’t have a fill-in bucket, but that’s due to it being infinite probably. If you’re looking for a collab site for doodling with your friends, that’s what you’re looking for! If you have any ideas on what could be added, you can always contact the devs, they usually respond and are super helpful :).
Update: I am happy to edit my review to inform everyone that now Whiteboardfox offers a bucket feature!
It is very good for doodling random ideas! make sure to have fun and keep being creative! It is down sometimes though ;-;
Witeboard - A real-time whiteboard for your team. No signups required.
Xmind - Xmind is a brainstorming and mind mapping application.
Mural - MURAL is a visual collaboration workspace for modern teams.
MindMeister - Create, share and collaboratively work on mind maps with MindMeister, the leading online mind mapping software. Includes apps for iPhone, iPad and Android.
Whiteboard Team - Draw, explain and collaborate visually in real-time.
MindManager - With MindManager, flexible mind maps promote freeform thinking and quick organization of ideas, so creativity and productivity can live in harmony.