There are a three tools you can use in the annotations toolbar to erase annotations you have created:
Undo Annotation button allows you to undo the last annotation. Keep clicking to continue erasing previous annotations. You can only undo your own annotations and not those of others. You can only undo your own annotations and not those of others.
Use the Pencil tool with colour set to white as an eraser. With this tool you can erase your annotations, those of other participants, as well as content in the original presentation. If you erase too much, just click undo.
Erase tool can be used to delete and entire annotation with one swipe. Simply swipe across the annotations you want to delete.
Delete tool allows you to select and delete an individual annotation. You must use the Select tool, select the annotation to delete and click the Delete button.
See attached screenshot to help identify all three tools.
