Apple obviously writes its own software for the iPhone, but Samsung's phones all run a customized version of Google's open-source Android, and Samsung is so dominant that it could very well split off and start building its own version of Android, just as Amazon did with the Kindle Fire.

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Assuming the expense allocation was reflective of how they would ultimatly split the money, the bottom line effect that it had could have been achieved with a well drafted partnership agreement.

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