Digital Therapeutic for Adolescent Depressive Symptoms in Cardiology and Gastroenterology

Inclusion Criteria: * 13-22 years of age at time of enrollment * Moderate-severe self-reported symptoms of depression at baseline (PHQ-8 \>=5) * Under the care of a US-based healthcare provider and willing and able to provide the name and contact information of the provider during consent * English fluency or proficiency and literacy of adolescent and consenting legal guardian, if required * Access to an eligible mobile device (capable of installing the app) and regular internet access * Willing to provide informed e-consent/assent and have legal guardian willing to provide informed e consent (if required) Exclusion Criteria: * Change in concurrent treatment (medication, and/or psychotherapy) for depression 30 days prior to study enrollment * Suicide attempt within the past year * Active suicide ideation with intent * Previously participated in user testing or clinical testing of the Spark app * Any condition, comorbidity, or event that, in the opinion of the investigator, will prevent the participant from adhering to the protocol or benefitting from the treatment (e.g., unable to perform informed assent or consent, treatment resistance as determined by investigator) or will prevent investigators from being able to ensure safety (e.g., will be leaving the country during study time period)