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 ;-;
Ziteboard - Ziteboard is an zoomable online whiteboard that lets team to collaborate in real-time.
Witeboard - A real-time whiteboard for your team. No signups required.
Mural - MURAL is a visual collaboration workspace for modern teams.
Smart Kapp Whiteboard - Connected whiteboard that saves notes to your app
Whiteboard Team - Draw, explain and collaborate visually in real-time.
Walls360 - Amazing wall graphics