Changing an appointment
In order to change an appointment, click on the corresponding item in the Calendar list, then click on the pencil button in the bottom left corner of the Detail view. In the Edit view, make your changes and click the Save button to commit the new information.
Deleting an appointment
If you need to delete an existing appointment, go to the Edit view, as described above, and scroll all the way to the bottom. There you will find the Delete button. Clicking on it will prompt you with a dialog message where you need to confirm the deletion.