How do I use the scissors tool?
Pinch to select a portion of the canvas. Once you have a selection you'll be able to move, duplicate, or delete it. Use the menu buttons in the top left to duplicate or delete. You can also double tap your selection as a shortcut to duplicate. Hit the 'Done' button to exit selection mode.
How do I add a device template?
Open the devices menu and choose the template you'd like to add. Once the template is added you can move or duplicate it the same way you would use the scissors tool.
Can I modify a shape after it has been created?
You can move or duplicate a shape by using the scissors tool, however you cannot modify it's size once it is placed. Think of the shape tool as a shortcut to drawing rather than a full blown vector editor.
How do I switch to an eraser?
The last tile in the color picker switches you to an eraser. This allows you to erase with your finger, Apple Pencil, or even the shape tool.
How do I use my finger to erase while continuing to draw with my Apple Pencil?
Library → Settings (top left). Toggle 'Draw' to 'Erase'.
How do I make shapes bigger than I can pinch?
Use both hands, it's easier to make shapes this way!
When using portrait or multitasking modes how do I zoom into the canvas?
Double tap the area you want to zoom into. Double tap again to zoom out.