This research aims to measure anew way of calories counting using a mobile app on weight loss and adherence to the mobile app. The participants should be adults who is overweight or obese and should have a smartphone with access to the internet. The participants will fill a baseline survey, take the height and weight measurements, watch a video about the use of the calories counting and app. A follow up visit will be in 4 weeks to take the height and weight measurements and fill a questionnaire. There is an option for the participants to continue with the research for additional 11 months with visit at 3, 6 and 12 months.

Obesity has been recognized as a disease by the American Medical Association in 2013. It has been alarmingly on the rise over the past two decades, especially in the MENA region. In Lebanon, 53.5% of the population is overweight and 18.16% obese. Self-monitoring, as part of behavioral interventions, is beneficial for weight loss, especially in the context of mobile application interventions. However, estimation of the food portions for proper food logging remains a challenge despite the use of databases, scales and household utensils.

Objective: To measure the efficacy of a novel 12-month self-monitoring program for weight loss and long-term adherence to the use of the application. The program entails estimation of food consumption using the hand and a mobile application (developed by the research team) that relies on evidence-based behavioral interventions.

Design: Randomized controlled trial Setting: American University of Beirut Medical Center Participants: Adults who are overweight or obese will be recruited from AUB/AUBMC staff and students and the community. Participants should be 18 years old and above and should have a smartphone with access to the internet.

Interventions: This research will be a three-armed randomized controlled trial. The first phase (I) will test three different methods of calorie counting each allocated to an arm of our trial at 4 weeks and the second phase (II) will test the long term efficacy of our method and its sustainability. One arm specific for the control group will be using a commercial mobile application called Fitness Pal (or رشاقة for Arabic preference) alone; another arm will be using the commercial mobile application Fitness Pal (or رشاقة for Arabic preference) along with the food estimation method using hands, and the third arm will be using the developed mobile application of the study along with the food estimation method using hands. Phase I constitutes a baseline and 4-weeks-visit where we will seek the participants' feedback concerning the mobile application and the hand counting method. Phase II: participants who are motivated to continue using the mobile applications and self-monitoring will be followed up to a period of one year.

Follow up visits will take place at 3 months, 6 months, and 12 months following the start of trial to assess for any change in participant's weight and adherence to the use of the mobile application and counting method.

Main Outcome Measures: The primary outcome of phase I will be the satisfaction with the counting method and mobile app mobile application rating and satisfaction with the various application features. The primary outcome of phase II will be the difference in the percentage of participants who achieved weight loss of 5% of their baseline weight among the three groups at 3 months, 6 months, and weight loss of 10% of their baseline weight at 12 months post-intervention.

Secondary outcomes include (1) a decrease in weight in Kg from baseline at 1,3,6 and 12 months; (2) a decrease in waist circumference in cm from baseline at 1, 3, 6, and 12 months, (3) frequency of logging in days, (4) adherence to the use of the application. In addition, demographics characteristics, self-regulation and internal motivation of the participants will be explored whether they affect any of the primary and secondary outcomes

Inclusion Criteria:

• Should have a smartphone with access to the internet
• BMI more than 25 (overweight or obese)

The participants will know the application they are using; the outcome assessor will be blinded to the user app when they fill the questionnaire and take the height and weight measurements