What are the key features of the new iPhone 13, and how does it compare to the iPhone 12? Your response should contain at least 4 sentences. Highlight at least 2 sections in your answer with markdown, i.e. *highlighted section*. Include keywords *camera improvement*, *battery life*, *A15 Bionic chip*, *5G*. In your response, the word *iPhone* should appear at least 3 times.
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