 Type 2 diabetes is a major and increasing problem in India and the UK. In clinical trials it can be prevented in people at high risk by lifestyle intervention. While these trials established the proof of principle, they involved a degree of input from healthcare professionals not feasible outside the trial situation. We hypothesize that diabetes prevention can be achieved at lower cost using personalised feedback via mobile phone, based on information on healthy diet and physical activity habits. We shall develop research protocols and computerized algorithms to test this hypothesis in India for application subsequently in the UK and elsewhere. 