With the advent of wearable digital health technologies, patient-generated health data (PGHD) will play an increasingly central role in evidence generation for medical device companies. Speakers on a recent FDA workshop advised that there are several barriers to the use of PGHD for evidence generation, however, such as the perennial headache of data interoperability and a new twist on the question of patient trust, problems that are likely to plague the field for the foreseeable future.