4-Fluorophenethylamine is primarily used in research and development within the field of organic chemistry, particularly in the synthesis of various pharmaceutical compounds. It serves as a key intermediate in the production of psychoactive substances, including certain stimulants and entactogens, due to its structural similarity to phenethylamine. Additionally, it is utilized in the study of neurotransmitter analogs, helping researchers understand the biochemical pathways and receptor interactions in the central nervous system. Its fluorinated structure also makes it valuable in the development of fluorinated drugs, which often exhibit enhanced metabolic stability and bioavailability.