iOS: status bar should be a part of app window as some animations have to go "under it"

Some iOS7 animations such as starting text input (e.g. try clicking on Search field in the Contacts app) require animation to go through-under the status bar (bat with signal level and clock), parts of screen "fly out" though-under the bar while Search field is being moved to top.

So statusbar is to be a part of the app window then and you should be able to paint/animate under it. Ideally the bar should be the optional as some apps need exactly whole screen.