AFMInfoBanner can be used to unobtrusively notify users about successful or erroneous events which do not require any specific action or UI locking. Good examples are network errors on the screens which can be functional even without the data that failed.
View is trying to find a navigation bar and show itself beneath it. If that fails, it shows from top of the window, adjusting height to be below status bar. View is resized to any text, but auto-hiding interval makes long text hard to read, so it's better to keep it short.