The Left Bar is a narrow gutter of controls on the leftmost side of the app. It contains a button to open and collapse the SmartPanel and controls that switch the SmartPanel view from Tools and Symbols to Insert Content, Shape Data, and Comments.
Collapsing the SmartPanel
You can collapse and open the SmartPanel as needed using the arrow button in the top left.
The SmartPanel has four different views you can toggle using the Left Bar.
The Tools mode is usually selected by default and you can toggle back to at any time by clicking on the toolbox icon. This view has all the essential tool palettes and symbols to complete your diagram. At the top, the tool set is a generic palette of popular tools like drawing shapes, lines, and text. This is followed by a series of diagram specific tool palettes and symbols.
You can switch to the Insert Content mode by clicking the + icon. This lets you add blueprints of other diagram types to your workspace and generate diagrams from data.
Click the database icon to toggle into Shape Data mode. Here, you can add data to any shape.
The last section will only appear if you already added comments to your diagram. If you have comments on shapes, you can switch to the Comments mode by clicking on the chat bubble icon. Here you can view the latest comments on shapes in your diagram.