Quick rebound of the login screen from the app.net iOS client: Twiggy.
Currently the Twiggy splash screen deviates from the platform's HIG because the entry screen might not always share the same layout, biggest offender being the login screen.
The idea here is to illustrate a login screen that is clearly out of the common application flow. ( the artwork displayed here is the original, not my original, I turned into a modal, which isn't ideal at all but serves the purpose )
It can be presented whenever necessary (first login/password has changed/etc), perhaps sliding in from the bottom so as not to break the other left/right existing animation metaphors.
This way, the splash could be optimized for the main application layout (nav/content/tab bar), and the login screen would slide in whenever necessary, creating a flow like:
splash --> stream -(slide up)-> login
Subsequent app launches would still honor the HIG and provide a smoother transition from splash to app.
Here's a similar idea that's been implemented in Path -> http://cdn.pttrns.com/pttrns/148/original/Path_Social-Networking.PNG
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