Silicon Labs’ app note on driving E-paper with their EFM32 micro. Link here (PDF)
Electronic Paper Displays (EPDs) are types of displays that are reflective and bistable. Reflective in this case means that they rely solely on ambient light and does not use a backlight. Bistable is the property of retaining an image even when no power is connected.
EPDs are commonly used in e-readers, industrial signage and electronic shelf labels. Their properties are ideal for applications which do not update the image frequently. Since the display draws no current when showing a static image, they allow for a very long battery lifetime.