Using a smart phone application to support meal replacement weight loss programs

Participants will receive an iPhone application that uses prompting, interactive feedback and planning and monitoring to support them on their weight loss program (a partial meal replacement program). Participants are prompted 3x a day by the phone to remind them to monitor their weight and food intake through a meal diary which provides real-time compliance feedback. The intervention will last 12 weeks. There is no requirement that the participant interacts with the app for a set time per day. The partial meal replacement program requires participants to replace 2 meals a day with two meal replacement shakes. Participants will acquire sachets from the study clinic to be made and eaten in a free-living scenario. Participants will be asked to follow the program for 24 weeks. The meal replacements are a new, confidential formulation and contain approx 1000kJ each.