Would I violate the HIG by showing a tab bar on my first view only? The first view also has a tableview and navigation bar at the top. Once the user selects a row, it goes to another tableview and no tab bar. The navigation bar is still at the top and the user can go back. Clicking a row from here displays the detail view. In summary, the tab bar will only be available on the first view.
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Technically, I know how to do this. But from the HIG and user point of views, I'm not sure about it. The tab bar is only needed on the first view to reach the in app purchase store. Guess this really constitutes a redesign where I have a new button on the first view? My navigation bar has just enough room for it in the top right.
I have done this too in my application and it has been approved without any issues. Besides, it is supported by UIKit, so I don't see any reason why it should be a problem. It's even perfectly logical to hide the tab bar when drilling down into a table.
I'd say go for it!