Electronic books (eBooks) and eReaders are now a commonplace tool in the reading experience for many readers. Yet these have long received mixed reviews. Designing suitable interactions that support successful eReading experiences is a relevant task. This paper reports on an exploration of orientation cue designs for electronic books through consideration of design techniques implemented in both physical books (pBooks) and eBooks. We executed a case study of contemporary pBook and eBook orientation cue designs and report on the results of a heuristic evaluation with a small set of expert evaluators. Our findings identify the need for further investigation of the design of orientation cues for both pBooks and eBooks.