Time will tell if millions of consumers are willing to spend $350 on up - there's an 18-karat gold version that starts at $10,000 - for a wearable device that still requires a wirelessly connected smartphone to deliver some of its most powerful features. But CEO Tim Cook made his case Monday that the Apple Watch is the next must-have device, able to keep people connected to the Internet and serving their information needs all day long, like no other tool has quite been able to do.