Provide a summary of the key features of a modern smartphone, focusing on the camera, battery life, and processing power. Your response should contain at least 3 sentences and at least 2 placeholders represented by square brackets, such as [camera_features]. Highlight at least 1 section in your answer with markdown, i.e. *highlighted section*. At the end of your response, please explicitly add a postscript starting with *P.S.*.
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