The purpose of this study is to evaluate the effectiveness of smartphone application for management of type 2 diabetes mellitus (DM).

Type 2 DM is an almost incurable chronic disease and continuous management is important for long-term prognosis. However, patient's compliance to conventional medical intervention is generally unsatisfactory and many patients feel difficult to access to the detail medical advice for type 2 DM.

Thus, the investigators developed a smartphone application for giving programed medical intervention to patients according to patients data; blood pressure, fasting blood sugar, body weight, calorie intake,exercise amount, etc.

Inclusion Criteria:

• Type 2 DM using oral hypoglycemic agent
• 6.5% < HbA1c < 10%
• systolic blood pressure > 130 mmHg or diastolic blood pressure > 80 mmHg
• BMI over 23.0
• 20 < age < 70
• smartphone user (android OS based)

Exclusion Criteria:

• Serum fasting glucose > 250 mg/L or post prandial 2 hour serum glucose > 350 mg/L
• systolic blood pressure > 180 mmHg or diastolic blood pressure > 110 mmHg
• Diabetes mellitus patient using insulin
• severe chronic diabetic complications (diabetic foot ulcer, severe diabetic retinopathy, diabetic nephropathy with severe proteinuria)
• congestive heart failure (NYHA III-IV or left ventricular ejection fraction < 30%)
• Aspartate aminotransferase (AST) or alanine transaminase (ALT) over 3 times of upper normal limit
• Serum creatinine > 1.5 mg/dL
• refusal to participate in the study
• drug addiction or alcohol addiction
• major psychiatric illness
• steroid treatment or hormonal treatment with changing the drug or drug dosage in 1 month
• changing dosage of antihypertensive agent, oral hypoglycemic agent or lipid lowering agent in 1 month
• malignant cancer
• pregnancy