Nokia's new flagship Lumia 1520 is big news and a big phone. The company's first "phablet" Windows Phone, it marks the debut of official 1080p screen support in version 8.1 of Microsoft's platform, not to mention a further distillation of Nokia's investment into PureView camera technology down into the mass market. It's also the device that Nokia hopes will rival top-tier iPhone and Android handsets that, so far, it has struggled to compete with. Plenty of high expectations, then, but does the Lumia 1520 live up to them? Read on for our first impressions.