Currently the whole world is going through an epidemiological crisis due to Covid-19, a virus which has a greater impact on people who are overweight or obese. Obesity represents a risk factor for serious illness and death from COVID-19. There is an enzyme that converts angiotesin-2, which is an enzyme that SARS-CoV-2 uses for entry at the cellular level, it is found in higher amounts in people with obesity. Among the group of people who can suffer from obesity are adolescents, who do not always maintain healthy eating habits or perform physical activities. In this research, a mobile application is presented to control and monitor the patient's body mass index according to their weight and height, making it known if they have obesity or any variant. In addition, it allows the patient to know the appropriate portions of daily food and to keep an own control of their physical activities and a history of their meals. That is why the objective of this research is to determine the impact that a mobile application can have on the obesity prevention process in adolescents. This study was carried out in Lima in 56 adolescents from 10 to 19 years old, in which 44.6% managed to improve their condition and 26.7% managed to stay in a normal condition.