For applications where security features are critical, you might want to provide a login screen that requires the BlackBerry® device user to log into the application on the BlackBerry device before using it. The UI classes provide simple password fields that hide the text entry with asterisk characters. Login screens might negatively impact the BlackBerry device user experience, and if the BlackBerry device user sets a password to protect the BlackBerry device, your application might not require a login screen.