The document discusses the potential for mobile phones to revolutionize health diagnostics in developing countries. It describes how researchers have turned smartphones into mobile microscopes by attaching additional lenses. This allows smartphones to diagnose conditions like malaria, tuberculosis, and parasitic infections from blood and sputum samples. The technology is currently being tested in several developing country contexts. The document also discusses initiatives to use smartphone spectroscopy and diagnostic apps to allow real-time analysis of health samples in remote locations.