OBJECTIVES: The use of Bring Your Own Device modalities in industry-sponsored clinical trials has presented numerous obstacles to adoption. Combining a patient diary with an existing eClinical BYOD application can help facilitate adoption. METHODS: A Phase 2, Randomized, Double-Blind Study of of a vaccination for HSV-2 is being conducted and requires the capture of a symptom and dosing diary prior to administration of the investigational product. In addition to a web-based eClinical application to manage this process, a study-specific application was designed to collect this information. This secure application was made available for iOS and Android devices, and individual site users downloaded the app to devices they provided on their own. Investigators were given the option to use either modality. All users were required to confirm their credentials every time they access the application, and to provide a confirmatory signature prior to submitting data. RESULTS: The first transaction was recorded in December 2014. Through December 31, 2015, 1,484 transactions were recorded. 556 transactions were included via web and 928 transactions were recorded via mobile BYOD application. Investigator adoption of BYOD has increased throughout the recruitment period, with 28% of all transaction recorded via mobile app during the first 30 days of recruitment, and 65% of transactions recorded via mobile app in December 2015. Compliance on diary completion showed no meaningful difference between web and BYOD modalities. CONCLUSIONS: This study demonstrated that investigators are willing to embrace and utilize BYOD in an RCT. With appropriate training, diary design, and app availability, BYOD can be an effective and useful mechanism for collecting patient data in a clinical trial.