The goal of this clinical trial is to compare those using a diabetes management smartphone application (mySugr) to those not using the application. This smartphone application is for Spanish-literate adults with poorly controlled, non-intensively treated type 2 diabetes (T2D). The main question\[s\] that it aims to answer are: * What is the impact of the use of mySugr (a smartphone-based application or app) with structured blood glucose monitoring on diabetes self-management among Hispanic/Latino adults with poorly controlled, non-intensively treated T2D? * Will diabetes self-management be more effective for those using mySugr (the Active group) compared to those not using mySugr (the Control group) over a 12-week study period? Participants will be screened and enrolled if they are eligible; they will have the study explained to them in Spanish or English and have time to ask questions and then sign an informed consent form. Clinical measurements (including height, weight, and blood pressure) and hemoglobin A1c will be done. All subjects will be given a blood glucose meter, lancing device, and blood glucose strips for the meter, and they will also receive an electronic scale. Several questionnaires will be answered. If a subject is randomly assigned to the Active group, they will download the mySugr PRO (professional) app in Spanish to their smartphone and be trained in its use. They will receive education focused on paired (before and 2 hours after a meal) blood glucose testing, which participants will conduct twice a day for 6 days and once a month for 3 months. Participants will continue structured blood glucose testing with the mySugr PRO app for 12 weeks, and they will have 3 virtual visits in Spanish with mySugr PRO coaches who will review the blood glucose records and advise the subjects. Subjects in the Control group will not receive the mySugr PRO app or coaching. They will continue with their usual diabetes management. All subjects will return after 12 weeks to return the scale and have a close-out visit with clinical measurements and questionnaires. Subjects will also receive a disturbance allowance for their time and participation.