A computer-implemented technique includes storing keychains in a memory of a computer. A login identifier and a password are received from a mobile device. The login identifier and the password are verified. Subsequent to the verification, one of the keychains is downloaded from the computer to the mobile device. The keychain includes N keys that are each associated with one of M physical locks of M locking devices, where N and M are integers greater than or equal to 1. The M locking devices or another locking device are monitored. Information in a key log is recorded when each of the N keys is used on one of the M locking devices or another locking device. The information includes a locking device identifier and a key identifier. The mobile device is alerted when each of the N keys is used based on the key log.