What are some alternatives?
When comparing Scribblar and Conceptboard, you can also consider the following products
OpenBoard - The OpenBoard software is an interactive white board software.
Sharepoint Online - SharePoint is a secure place to store, organize, share, and access information from almost any device.
IDroo - A shared whiteboard for use by multiple Skype-users simultaneously. Features
Huddle - Huddle | The Enterprise Content Collaboration Platform
Twiddla - Mark up websites, graphics, and photos, or start brainstorming on a blank canvas.
Podio - Podio is the online work platform. Manage, share, and get your work done smarter together with tools that work like you. Free for 10 Users.