Participants willing to use FreesStyle Libre CGM according to manufacturer instructions, document insulin delivery, meals, and daily activities.
Participants have a smartphone compatible with study requirements.
Participants are willing and able to sign a written informed consent form to use their data.
Participants are willing to use the bolus calculator for insulin dosing (only for segment 1)
You may not be if
1. Concomitant diseases/treatment that influence metabolic control or any significant diseases/conditions including psychiatric disorders and substance abuse or drug or alcohol abuse that in the opinion of the investigator is likely to affect the subject's ability to complete the study or compromise patients' safety.
2. Relevant severe organ disorders (diabetic nephropathy, diabetic retinopathy, diabetic foot syndrome) or any secondary disease or complication of diabetes mellitus, such as:
1. Subject has unstable or rapidly progressive renal disease or has eGFR \< 45 or is receiving dialysis
2. Subject has active proliferative retinopathy
3. Active gastroparesis
3. Participation in any other interventional study
4. Female participant who is pregnant or planning to become pregnant within the planned study duration
5. Individuals who are using one of the following types of insulin:
1. Intermediate-acting insulin (NPH)
2. Mixed insulin like:
i. Premix NPH/ Regular (e.g. Humalin 70/30, Novolog 70/30) ii. Premix analogs (e.g, Novolog mix 70/30, Hu,alog mix 75, 25, Humalog Mix 50/50) c. Inhale insulin (e.g. Afrezza)
6. Hypoglycemia unawareness
7. Individuals who are treated with intravenous (IV) insulin injections, or a combination of insulin injections and/or IV insulin and insulin pump therapy.
8. Individuals who have extensive skin changes/diseases at the proposed application sites that could interfere with device placement or the accuracy of interstitial glucose measurements.
9. An episode of diabetic keto-acidosis within the month prior to study entry and/or severe hypoglycemia resulting in seizure or loss of consciousness in the month prior to enrolment.