The iLet Experience Study

Inclusion Criteria: * Users must meet the following criteria in order to be enrolled in the study: 1. Diagnosed with type 1 diabetes and prescribed the iLet Bionic Pancreas System 2. At least 6 years of age 3. Using or planning to use either U100 Novolog (insulin aspart) or U100 Humalog (insulin lispro) in ready-to-fill cartridges, or U100 Fiasp® PumpCart® (insulin aspart) in pre-filled 1.6mL cartridges 4. Willing to provide HbA1c results obtained within the 6-month period prior to starting use of the iLet and during the last 6-months of study participation 5. Willing to provide CGM data, if available, obtained in the 1-month period prior to starting use of the iLet 6. For females, not pregnant or planning pregnancy in the next 12 months 7. Able to respond to alerts and alarms, and to provide basic diabetes self-management 8. Reside full-time in the US 9. Able to speak and read English 10. Willing and able to download the iLet Mobile App and keep it active throughout the study and upload device data regularly 11. Willing to answer baseline survey, monthly surveys, and share CGM data, and follow-up data, as necessary Exclusion Criteria: * Users with the following characteristics will not be considered candidates for the study: 1. Type 2 diabetes, cystic fibrosis-related diabetes, congenital hyperinsulinism, pancreatogenic diabetes, or any form of diabetes mellitus other than type 1 diabetes 2. Use or planned use of any insulin in the iLet other than U100 Novolog (insulin aspart) or U100 Humalog (insulin lispro) in ready-to-fill cartridges, or U100 Fiasp® PumpCart® (insulin aspart) in pre-filled 1.6mL cartridges 3. End-stage renal disease on renal replacement therapy (peritoneal dialysis or hemodialysis) 4. Use or planned use of hydroxyurea