Background Digital Health Technologies (DHTs) have shown potential to improve health outcomes through improved medication adherence in different disease states1,2. Cystic Fibrosis (CF) requires care coordination across pharmacies, patients, and providers3,4. DHTs can potentially support patients, providers, and pharmacists in diseases like CF, where high medication burden can negatively impact patient quality of life and outcomes. Methods In this prospective cohort study, a CF-specific mobile application (Phlo) was distributed to adults with CF who received care at the University of Utah Cystic Fibrosis Center, used an iPhone, and filled prescriptions through the University of Utah Specialty Pharmacy services. Participants were asked to use Phlo for 90 days with an optional 90-day extension period. Participants completed four surveys at baseline and after 90 days. Changes in patient-reported outcomes, adherence, clinical outcomes, and healthcare resource utilization from baseline to 90 days were tracked. Results Phlo allowed users to track daily regimen activities, contact their care team, receive medication delivery reminders, and share progress with their healthcare team. A web-based dashboard allowed the care team to review reported performance scores from the app. Most patients (67%) said the app improved confidence in and motivation for continuing their regimen. The most important reported benefit of Phlo was having a single location to manage their whole routine. Inpatient hospital admissions decreased from 12 during the baseline period to 7 after the 90-day study period. Conclusions: Phlo is a mobile health technology designed to help patients with CF manage their treatment regimen and improve patient-provider communication.