The RCSB Protein Data Bank (PDB) mobile app is the official mobile app of the RCSB PDB. It provides fast, on-the-go access to the RCSB PDB resources. The app enables the general public, researchers and scholars to search the Protein Data Bank and visualize protein structures using either a WiFi or cellular data connection. Search the entire PDB database, view the latest protein structure entries to be released, access your MyPDB account, view the entire catalog of Molecule of the Month and more. This work has been funded by National Science Foundation grant DBI 0829586.