Healthy Jeart is a free app targeted to young people. It is especially designed to foster a healthy lifestyle. Young people can find in it practical recommendations about seven areas of health and a game through which they can consolidate the acquired knowledge on different healthy and beneficial elements. Healthy Jeart is also useful for healthcare professionals and educators. The latter can find in it educational proposals in the subject that can be implemented in schools and challenges in which they can get students to participate and compete. Healthy Jeart has been awarded the distinction of Health App by the Andalusian Agency for Health Quality and is supported by the Community Nursing Association (CNA) at the national level. Healthy Jeart is a health promotion tool that was created with a low cost; however, the impact on the physical, psychological and social well-being of young people is expected to be high. The present article describes its design, production, revision and evaluation process. The design of this tool required knowing how young people perceived it and determining the contents that should be included in it. Such information was gathered through eight nominal groups. Once the first prototype was available, this was tested with a sample of adolescent students. With the accreditation procedure, given the attended improvements to pass it, the current version of the application was reached.