I have a UITabViewController
set up with two tabs, the second containing a web browser. The keyboard will not appear in my App unless I first display and dismis
Not a lot to go on but if you have textfield visually displayed but it will not evoke the keyboard when tapped then most likely you have an issue with focus i.e. the view containing the textfield does not believe it should intercept taps. This usually occurs because another view is visually in-front (below in the logical view hierarchy) of the view containing the text field. Presumably, displaying and then dismissing the alert alters the view hierarchy and lets the textfield intercept taps.
That's what I would check first.