Dengue hemorrhagic fever is an endemic disease that can cause severe bleeding, a sudden drop in blood pressure (shock), and even death. This severe form of dengue is characterized by an abrupt decrease in platelet count, often requiring blood transfusions to halt hemorrhages. Traditionally, platelet counting is a standard procedure, relying on peripheral blood smears, Giemsa staining, and microscopic observation. While routine in well-equipped clinical laboratories, this method becomes unfeasible in underprivileged or remote areas lacking access to proper facilities. We developed a cell phone accessory that transforms smartphones into a portable microscope, resolving micron-sized structures and providing high-quality images of biological components. This allows for simple and reliable platelet counting, even in challenging environments, ultimately facilitating timely referrals to more advanced medical centers.