Propylammonium lead iodide is primarily used in the development of perovskite solar cells, which are known for their high efficiency and low-cost production. This compound is a key material in the light-absorbing layer of these cells, enabling efficient conversion of sunlight into electrical energy. Its unique properties, such as excellent light absorption and charge carrier mobility, make it a promising candidate for next-generation photovoltaic technologies. Additionally, it is being explored for use in optoelectronic devices, including light-emitting diodes (LEDs) and photodetectors, due to its tunable bandgap and strong luminescence. Research is ongoing to optimize its stability and performance for broader commercial applications in renewable energy and electronics.