4,4'-Azoxydiphenetole is primarily used in the field of liquid crystal research and development. It serves as a key component in the synthesis of liquid crystal materials, which are essential for displays in electronic devices such as LCD screens. Its unique molecular structure allows it to align in specific orientations when subjected to electric fields, making it valuable for creating stable and responsive liquid crystal phases. Additionally, it has been explored for its potential in photonic applications, where its light-modulating properties can be utilized in optical devices and sensors.