In 2011, the United Nations Security Council adopted resolution 1983, which calls for an end to sexual violence as part of an approach to address HIV in conflict and post conflict settings.
The same devices can also be used as public address systems, projecting instructions or warnings at lower settings and at higher settings, forcing crowds to disperse.
By default, it works with your Apple ID e-mail address, but you can add as many as you'd like from the settings application after verifying that you do indeed own the account.