The objective of this trial is to test whether a smartphone app, SMART-IBD, is effective in improving medication adherence and self-management skills in adolescents with IBD. The investigators will conduct a randomized control trial to compare a sample of 20 youth (ages 13-17) with IBD using an app that has educational content and medication reminders to 20 youth in an attention control group. The length of the intervention will include one month of baseline adherence data collection, one month of intervention, and one month of post-treatment adherence data collection.

Inclusion Criteria:

• Patient diagnosed with Crohn's disease, ulcerative colitis, or indeterminate colitis (collectively IBD)
• Prescribed at least one medication used to treat IBD, regardless of route of administration
• Access to internet or wi-fi or data plan and access to smartphone
• English fluency for patient and clinician

Exclusion Criteria:

• Diagnosis of pervasive developmental disorder in patient or caregiver as determined by medical chart review
• Diagnosis of serious mental illness (e.g., schizophrenia) in patient or caregiver as determined by medical chart review

The study PI, statistician, co-investigators, and all personnel who are involved in endpoint assessments will be blinded. Only study coordinators will have access to the assignment of each participant.