For Curio Standard and Professional customers, the tools palette includes a brush and eraser tool so you can sketch out an idea or drawing.

Inevitably, while brainstorming or thinking through an idea, you may need to sketch something out when the keyboard just won’t do. Fortunately, Curio has a scribble mode with sketching tools built right in, so you don’t have to stop and launch another application when inspiration strikes.

Curio comes with several pens and brushes to use when drawing, including a pencil, ballpoint, felt tip, paint brush, and highlighter. Each stylus has different settings for color, line thickness, and opacity that have been configured to mimic the real world object that it represents. Using the inspector you can change the color, brush thickness, and opacity of any stylus.

The Scribble “Onionskin”

While sketching, your scribbles will appear on top of all other figures and items on the idea space. The scribble layer acts as an onionskin appearing on top of your idea space’s figures.


If you have Curio Pro this means your scribbles appear top of all your figure layers. Curio doesn’t currently support a scribbles per figure layer as the current architecture would make this far too memory intensive.

Keyboard Shortcuts

You can press the B key on your keyboard to quickly choose the brush tool. Press E to choose the eraser.

Apple Pencil

Many of the styluses are also fully pressure-sensitive when used with an iPad with Apple Pencil connected via the macOS Sidecar feature, or a graphics tablet such as those made by Wacom, whereby the brush size and color saturation may change while you are drawing based on the pressure applied to the pen.

Curio also supports iPad sketching via Luna and Duet although you need to set a different pressure sensitivity multiplier. And if you use an XP-Pen tablet then you may need to tweak this setting.

Draw with a Pen or Brush

  1. Click on the Brush tool in the toolbar and choose the brush or pen you want to use. Note for super-responsive mouse handling the idea space will temporarily go into Quick Render mode where shadows are hidden and text rendering is optimized.
  2. You can quickly choose a color from the narrow color palette in the inspector bar or the much larger color palette in the inspector shelf. On the far left of the inspector bar’s color palette, or at the top of the inspector shelf’s palette, you can see the current, active color. If you click that color control then you can bring up Apple’s standard color picker to choose any color.
  3. Begin drawing in the idea space. While in scribble mode, you can continue to change the brush attributes or choose a different brush or pen from the inspector bar.

Erase a Portion of Your Drawing

  1. Click on the Eraser tool in the toolbar or inspector bar and “draw” where you want to erase. You can even change the size of the eraser using the inspector.
  2. Alternatively, you can use the Select tool in the toolbar to drag-select a region then press the Delete key to delete it. You can hold down the ⌥ (Option) and ⌘ (Command) keys while dragging to select only your scribble and not any figures or other items on the idea space.
  3. Lastly, if you are using a graphics tablet that has a pen with an eraser tip, you can simply turn the pen over to erase a portion of your drawing.

Convert a Scribble to an Image Figure

  1. Using the Select tool in the toolbar drag-select a region. You can hold down the ⌥ (Option) and ⌘ (Command) keys while dragging to select only your scribble and not any figures or other items on the idea space.
  2. Choose Edit > Convert Selection to Image Figure.
  3. You now have an image figure that you can treat as a normal figure on the idea space: give it a border, move it above or below other figures, or even add it to a list or mind map.

Convert a Figure to a Scribble

  1. Using the select tool in the toolbar (looks like a mouse arrow pointer) select one or more figures.
  2. Choose Edit > Convert Selection to Scribble.
  3. You can now use the scribble layer’s pens, brushes, and eraser to modify the figure.

Scribble Inspector

When in scribble mode the inspector bar and inspector shelf changes to reveal handy controls for working with the pens and brushes.

Brush Palette

Click a brush to activate it. Each brush’s color and inspector settings are independent from each other.

Brush Color

Displays the current brush color. Click to bring up the standard Mac Colors picker.

Color Palette

The scribble inspector displays the full, large-sized 13x10 matrix displaying 10 shades each of grays and colors. The inspector bar shows a more compact strip with only 5 shades each of grays and colors.

Brush Size, Opacity, and Pressure Sensitivity

Set the size and opacity of the currently selected brush.


You can change the brush size on-the-fly with the [ and ] keys on your keyboard.

If you’re using a pen-based graphics tablet, like a Wacom tablet or an iPad with Apple Pencil connected via the macOS Sidecar feature, then the brush size and color can be pressure-sensitive if those toggles are enabled. In that case the specified brush size and opacity is the maximum size given a maximum amount of pressure.

Click the Reset Brush to reset the selected brush to its factory defaults.


You can choose whether the scribble on an idea space is printed, exported, or presented.