When ever you draw something on the whiteboard it becomes an object that you can interact with by using the selection tools and the inspector. This allows you to adjust the various properties of an object like size and positioning without having to erase and redraw an object. See the Interacting with Objects section of the FAQ for more tips.
You can set the line drawing options by performing a long press on the
icon, you will be presented with the following popup for adjusting the line settings.

You can adjust the fill setting for new shapes to draw by performing a long press on the
icon and you will be presented with a popover like the one below that will allow you to turn on the fill option.

You can adjust the font setting for new text boxes and labels by performing a long press on the
icon and you will be presented with a popover like the one below that allows you to adjust the font family and size.

You can select an object by tapping the
icon on the tool palette and then tapping the object. Alternatively, you can 2-finger tap an object to immediately select it from any mode
Once you have selected an object you can perform a 2-finger tap and you will be presented with a popup menu that has a delete option, just tap delete and it will disappear.
When you are in selection mode
you can tap on an already selected object to select the next object below it. As you continue to tap the next lower object will be selected each time until there are no more objects below and then the top most object will be selected again.
When you are in selection mode
you can tap and drag a selection box around multiple objects once you release all objects will be selected.
Select the shape you want to add the label to and then perform a 2-finger tap on it to bring up a popup menu like this one.

Select the Label option and you will be presented with a keyboard to enter a label for the shape.
Select the text that you want to adjust and then tap the inspector icon (
) in the top toolbar. Scroll down to the Font option and tap it to adjust the font properties.
You can use the My Diagrams button in the toolbar to go to the Diagram Gallery where you can manage any of your saved boards. All of the boards will be listed in the order they were last used with the most recent appearing first. You can move between pages by swiping left or right.
When you are in the Diagram Gallery you can change the name of the board by tapping on its name and entering a new name.
You can use the
icon below the board's name to delete an existing board.
Once you have created a board you want to use as a template you can duplicate the board from the Diagram Gallery by using the
icon below the board's name. The original board will be unchanged and you will start with the contents of the original on a new board.