What's coming to the iPhone 18 Pro remains largely a mystery, as we're still several months away from Apple's next big reveal. With a new CEO stepping in right before Apple announces its next iPhone, the company will almost certainly want to make a splash, and dropping massive camera upgrades is one way to do that.Rumors from the Weibo-based leaker Digital Chat Station in China suggest that Apple has a four-part plan to upgrade iPhone cameras.Step 1 — iPhone 18 Pro variable aperture (Image credit: Future)The company plans to start with a variable aperture on the iPhone 18 Pro, allowing…