Speculation about a fall release of the latest iPhone is already rampant, but there’s a new twist this year: questions about Apple’s ability to wow an increasingly competitive industry. The iPhone 4S, unveiled last October, offered only marginal improvements over the previous version, and the Siri voice assistant has yet to become a new mobile standard. And while the iPhone’s pixel-packed retina display remains the sharpest on the market, Asian rivals like Samsung are drawing on their flat-panel-TV knowledge to go brighter and more vivid. “The iPhone’s display is starting to look dull,” tech blog Boy Genius Report mused recently. Though the Apple juggernaut still looks unstoppable, its product cycle appears to have slowed. The late Steve Jobs, Apple’s visionary co-founder, would no doubt have screamed at Apple’s engineers many months ago. We’ll soon find out whether his replacement did the same.