This document discusses, among other things, an apparatus comprising a pump configured to deliver insulin, a processor, and a user interface including a bistable display. A display element of the bistable display is placed in one of two stable orientations upon application of a biasing voltage and stays in the stable orientation when the biasing voltage is removed. The processor includes a display module configured to display a non-blank reversion display screen on the bistable display when no input is received at the user interface after a specified time duration, and to recurrently change the reversion display screen until input is received at the user interface.