D-tree is an NGO that develops clinical protocols and mobile applications to improve healthcare in developing countries. They implemented a project in Malawi that equipped health workers with phones containing an app to assess and treat under-5 children per national guidelines. Over 20,000 children have been assessed using the app, which has led to better adherence to guidelines, automated reporting, and improved confidence in health workers' abilities. However, challenges include stockouts, network issues affecting data syncing, and eyesight problems for some health workers. D-tree plans to expand the project and add new features like malaria testing.