Every February mobile phone manufacturers, networks, suppliers and retailers descend on Barcelona for the Mobile World Congress, and with the industry developing at an astonishing rate I kept a close eye on this year's event.

The men from Sony had a few neat tricks, but the company is struggling to differentiate itself from its competitors these days. It's understandable – there is only so much you can add to a four-inch glass slab running someone else's software. The company's latest unique design feature, though, to cycle a rainbow of colours through a large plastic aperture at the bottom of the handset, is just plain gaudy.

Taiwanese handset juggernaut HTC appeared on a firmer footing, consolidating its Android models under a series called One. The entry-level One V sports a 3.7in display and a five-megapixel camera. The One S bumps the display up to 4.3in and the camera up to 8MP, while the range-topping One X has specs that would embarrass most laptops, including a 1.5GHz dual-core processor.

All One-series models run the latest version of Android, known as Ice Cream Sandwich, and come with 25GB of free online storage, five times as much as Apple's iCloud.

Nokia, meanwhile, demonstrated its increasingly eccentric approach to business with impressive yet baffling product launches. It's just over a year since Nokia announced a strategic partnership with Microsoft designed to revive Nokia's smartphone sales and give Microsoft a massive platform for its Windows Phone operating system.

Twelve months on that partnership is beginning to bear fruit. Nokia's Windows-powered Lumia range has had good press and last week Nokia added two new models. The high-end Lumia 900 sports an iPhone-beating 4.3in display and will reach the UK in April while the entry-level Lumia 610 is expected to go head-to-head with budget rivals running Google's Android.

It was odd, then, to see Nokia gazump its own new range with the 808 PureView (pictured right), a chunky camera cum phone with a headline-grabbing 41MP sensor (that's five times more than the iPhone 4S). The really strange bit? It's based around the company's outgoing Symbian operating system.

The PureView concept is sound – adding a high-quality image sensor, sharp lens and proper xenon flash to a phone will tempt many amateur photographers who still carry a phone and a compact camera. But to introduce these features on an outgoing operating system seems silly, and to announce it at the same time as the somewhat bland range you're trying to flog – well, that's insane.