Researchers in Singapore have developed the world's smallest LED (light-emitting diode) that enables the conversion of existing mobile phone cameras into high-resolution microscopes. Smaller than the wavelength of light, the new LED was used to build the world's smallest holographic microscope, paving the way for existing cameras in everyday devices such as mobile phones to be converted into microscopes via only modifications to the silicon chip and software. This technology also represents a significant step forward in the miniaturization of diagnostics for indoor farmers and sustainable agriculture.