If you're wondering why the under-screen camera on the iPhone Duo's inner display isn't placed in the top-right corner, Chinese leaker Instant Digital has provided an explanation. "The iPhone Duo's under-display camera wasn't placed in the top-right corner of the inner screen because of engineering difficulties," said the leaker in a Weibo post this morning. "The next generation will likely move it there, aligning it perfectly with the outer screen's camera." That sounds like a real engineering challenge, since the opposing rear cameras are the thickest things in the whole phone, but let's wait and see.