 Metal halide perovskites are promising materials for optoelectronic applications due to their high efficiency and low cost. However, one of the main concerns is the potential for ion migration, which could lead to device degradation over time. Studies have investigated the mechanisms behind ion migration and proposed strategies to reduce its effects. Additionally, researchers have begun exploring the possibility of utilizing ion migration as a tool for enhancing device performance. This article was authored by Jean-Wook Lee, Solji Kim, Junim Oh-Yong, and others.