What's on mobile's menu in Barcelona this year?

The biggest date in mobile's calendar is almost upon us again as the Mobile World Congress trade show kicks off in Barcelona next Monday. What are the key themes to watch out for at this year's event? Natasha Lomas picks the top three.

Mobile broadband
It was big last year - with much self-congratulatory industry back-slapping over how the mobile internet had finally come of age with the help of HSDPA networks (and, in a marketing sense, the iPhone). 2008 really turned out to be mobile broadband's year - with dongle mania, buckets of iPhone-esque webby devices and the seductive promise of all-you-can-eat data.

This year mobile broadband is more important than ever - in tough economic times it is the great revenue hope of operators. And topping the bill of MWC keynotes on Tuesday is a session on 'Sustaining growth in challenging times'. Pay-as-you-go mobile broadband anyone?

Of course there is already a snake in this mobile garden - analysts are making concerned noises that operators may well be overstretching their networks by offering all-you-can-eat tariffs. Especially as this kind of data gobbling doesn't necessarily bring increased riches but does require more network investment to ensure good quality of service for all users. That opens up the awful prospect of mobile broadband actually becoming painful to operators' bottom lines.

So expect a lot of talk about strategies for monetising the mobile internet. And not just on smart phones, which remain a niche, high end portion of the market. Mobile widgets - simple web apps that can make an impact on the mass market of lower-end mobile and feature phone owners - are likely to be a hot area too.

Which brings me to the next theme...

Apps
Rumours are flying around of a couple of very big cheeses launching their own app shops - to rival Apple's rampantly successful iPhone App Store. Microsoft and Nokia have both been mentioned as readying app stores - though are yet to make official announcements.

The mobile industry is certainly banking on software to differentiate between the increasingly similar hardware offerings in play. (Smartphone specification sheets read like check lists these days: worthy only of comment when a 'key feature' such as wi-fi is missing.) And having a healthy developer community creating lots of juicy apps is the desired way to with it. How do you create a healthy developer community? There's no foolproof success recipe - but having a user-friendly store front that enables apps to easily be found, rated and bought is certainly a must these days.

This year's show will also include, for the first time, an 'Application Developers Garage' - which promises to bring "developers, engineers and communities from across the mobile application value chain into one place". They even get their own real-time app competition - which sounds reminiscent of demo developer community parties from the Atari/Amiga era. Yup, the serious geeks are definitely in demand alright.

Android
With no official Apple presence at MWC there's more time and space for Google's Android - which generated truckloads of interest last year despite there being only a handful of prototypes on show. Since then the G1 has launched but rumours are coming thick and fast of more Android devices poking their heads above the parapet in Barcelona.

The Android OS is famously open source and the first Android device (the G1) is famously exclusive to T-Mobile so if we don't get any news of the follow-up G2 I, for one, am prepared to eat my hat.

But it's not just T-Mobile - rumours of other mobile makers and operators offering Android devices are coming thick and fast, from previously Windows Mobile-loving hardware makers HTC and Samsung, to operator Vodafone.

Another sign it might just be Android's year? Microsoft's Steve Ballmer will be speaking on the unlikely topic of 'Moving Towards an Open Mobile Ecosystem'. Which suggests at least a hairline crack appearing in the proprietary gate that is Windows Mobile.