Codesign and Feasibility Testing of a Tool to Evaluate Overweight and Obesity Apps

Background: Digital health interventions and mobile technologies can help to reduce the rates of obesity and overweight conditions. Although weight management apps are widely used, they usually lack professional content and evaluation, so the quality of these apps cannot be guaranteed. The EVALAPPS project aims to design and validate a tool to assess the safety and effectiveness of health-related apps whose main goal is to manage and prevent obesity and overweight conditions. Objective: The aim of this paper is two-fold: (a) to co-create and codesign the EVALAPPS assessment tool and (b) to pilot its feasibility among overweight and obese individuals that use weight control apps. Methods: A mixed-methods approach was used. A multidisciplinary team ( n = 12) participated in a co-creation workshop to provide proposals and inputs about the look and feel of the content, usability aspects, appearance, sections, and main features of the EVALAPPS tool. The tool was tested for its feasibility among 31 overweight and obese individuals, attending the CP Endocrinologia i Nutrició SL Clinic for the first time. Participants were asked to use a specific weight control app [Yazio (YAZIO GmbH, Erfurt, Germany), My FitnessPal (MyFitnessPal, Austin, TX, USA) or MyPlate (MyPlate, Santa Monica, CA, USA)] for two weeks and then evaluate them by using the EVALAPPS (EVALAPPS, David Ganyan, Barcelona, Spain) (June 2020, David Ganyan, Barcelona, Spain) tool. Seven participants were phone interviewed to gain more insight into the use of the EVALAPPS tool. Results: The co-creation workshop allowed conceptualizing the EVALAPPS tool. The feasibility study showed that all criteria from the Usability and Functionality dimensions had valid answers, while Reliability, Security, Privacy, and Health indicators were the dimensions with less valid answers. In all three apps, the dimension with the highest score was Usability/functionality, followed by app purpose. Clinical effectiveness and Development were the dimensions with the lowest scores in all three tested weight control apps. Conclusions: The participation of the multidisciplinary team and end-users in the conceptualization and testing of a tool to assess health apps was feasible and relevant for the usability of the tool.