Digital Therapeutic for Adolescent Depressive Symptoms in Hematology, Oncology, and Weight Management

Inclusion Criteria: * Between the ages of 13 and 22 * Moderate- severe self-reported symptoms of depression at baseline (PHQ-8 \>= 5) * Have a comorbid medical condition and under the care of a healthcare provider at CHST * English fluency and literacy of adolescent; English or Spanish fluency and literacy of consenting legal guardian if under 18 * Access to a compatible smartphone (or other device) and operating system (i.e., capable of installing the app from the Google Play or Apple App Store; list will be provided to participants) and regular internet access * Willing to provide informed consent/assent and have legal guardian willing to provide informed consent (if required) Exclusion Criteria: * Concurrent psychotherapy: Have met with a psychologist for intervention (not assessment) for 30 minutes or more, more than once in the 3 weeks prior to enrollment as determined by the study team * Change in psychotropic medication (initiation or change in dose) within the past 30 days prior to enrollment * Suicide attempt within the past year as determined at eligibility screening * Active suicidal ideation with intent as determined at eligibility screening * Previously participated in user testing or clinical testing of the Spark app * Participating in any other psychiatric or psychological treatment based clinical research at the time of enrollment and up to two months prior to enrollment or planning to participate in any other psychiatric or psychological treatment based clinical research during the study intervention period (5 weeks) * Any condition, comorbidity, or event that, in the opinion of the investigator, will prevent the participant from adhering to the protocol or benefiting from the treatment (e.g., unable to provide informed assent or consent) or will prevent investigators from being able to ensure safety (e.g., will be leaving the country during study time period)