Use the ruler as a guide for drawing precise lines.
Access Ruler
- Access the ruler quickly with a two finger tap and hold.
- Tap on the three Vertical Dots icon and then "View > Ruler."
Dismiss the Ruler
- Tap on "View > Ruler," two finger long press, pinch, or swipe off the edge of the screen.
Adjust Ruler Unit
- Go to "Notability Settings > Document > Ruler Unit."
Stamp
- Double tap with one finger on the ruler to stamp.
- Use the blue triangle anchors to measure and adjust them to change the width of your stamp.
Cheat Sheet
- Two finger long press on the note to show the ruler
- Two finger long press or two finger pinch and swipe off the edge to dismiss the ruler
- Two finger to pinch and adjust the ruler
- One finger moves the ruler
- One finger double tap to stamp a line
- One finger tap on the compass to round to the nearest 45º
- Two finger tap on the compass to rotate by 90º counterclockwise
- Vertically pan (slide) the compass to rotate the ruler
- Use fingers to slide the triangles on ruler, which will adjust the line length
- You can move both triangle anchors at the same time
- Stamp preview will appear only when holding or moving the triangle anchors
- Hold down on a triangle to show the target line
- Switch to hand or text tool to dismiss the ruler
- Line detection will snap the line to the ruler even if you started the line away from the ruler
Available for 
subscribers on iOS only.