Background and Objectives: eHealth technologies and tools can be effective instruments to address the challenge of ageing in EU, providing an opportunity to improve the health and well-being of older people by enabling access to knowledge and improving relationships with peoples environment, and ensuring the sustainability of health systems. Within Gatekeeper European project, the Basque Country region (Spain) has implemented a community-based intervention to assess the effectiveness of MAHA App for the promotion of healthy lifestyle habits among Basque elderly people. Methods: This quasi-experimental and longitudinal study Aims to approach 10000 people aged 65+ and/or their caregivers. The community-based intervention is boosted by the community network that involves more than 39 community organizations belonging to the Basque Health Ecosystem. The MAHA App, the health asset promoted, is a self-managed tool that offers contents and materials to reinforce socialization; foster health literacy and empowerment; and promote healthy lifestyles. A mixed method approach is being carried out, using quantitative techniques, through validated questionnaires and metrics; and qualitative techniques, to collect user experience and identify the determinants, factors, and aspects of the intervention impact, and user engagement. Results: The monitoring data shows that the actions implemented are effective, as the intervention has been widely disseminated and almost 5,000 people have accepted to participate. However, only 5% finally registered in the application. This intermediate Results shows low adherence to the intervention and a high level of dropout, as it is understood that once the user has agreed to participate, he/she has not followed the study protocol (defined as downloading the app, registering, and using it). Conclusions: The community-based intervention implemented in the Basque Country will contribute to generating awareness and new data on research into the intention-to-treat, adherence, and attrition rate of the use of eHealth applications self-managed by the elderly. clinicaltrials.gov identifier: NCT05614479