Real-time Engagement for Learning to Effectively Control Type 2 Diabetes

This is a clinical trial that includes a run-in period, a 90 day micro-randomized trial, and a 90-day observational period. The goal of this study is to evaluate whether providing paired real time glycemic and health behavior data in a smartphone app leads to better glycemic control among adolescents and young adults with T2D. Glycemic control will be monitored using Continuous Glucose Monitors (CGM), and health behavior data will be collected via a Fitbit activity tracker and a research app (Healthmine). Participants will be prompted to view and reflect on glycemic trends and health behavior data (Fitbit data, logging of diet and medication adherence) during the 90-day micro-randomized trial period, then observed for ongoing use of the Healthmine app and engagement with CGM in the following 90-day observation period.

Inclusion Criteria: * type 2 diabetes: negative diabetes autoantibodies, no suspicion for monogenic diabetes * HbA1c ≥7.0%, stable medication use * HbA1c 6.0-6.9% without short-acting insulin, any other stable diabetes medication use * English-speaking (app in English) Exclusion Criteria: * Current pregnancy * Hydroxyurea use (CGM sensor inaccuracies) * Cognitive impairment or severe psychiatric condition that could interfere with participation in behavioral intervention for diabetes self-management * Current or previously diagnosed eating disorder