Azobenzene-3,3'-dicarboxylic acid is primarily used in the development of photoswitchable materials due to its ability to undergo reversible trans-cis isomerization upon exposure to light. This property makes it valuable in the field of smart materials, where it can be incorporated into polymers, gels, or surfaces to create light-responsive systems. It is also employed in the design of molecular machines and nanoscale devices, where its light-induced structural changes can be harnessed for controlled motion or function. Additionally, it serves as a building block in supramolecular chemistry for constructing dynamic, light-triggered assemblies. Its applications extend to photopharmacology, where it can be used to develop light-activated drugs for precise therapeutic control.