We are spoilt for choice when it comes to mobiles, but what really matters when we choose our next one – price, function or network?

If you’re setting out to buy or upgrade a mobile phone, however, there are three crucial questions to consider: what do you want to do with it, how much do you want to pay and which network do you want to be on?

The first question is simply not one that would have been asked a few years ago. iPhones and handsets made using Google’s Android operating system now let you listen to music, surf the web, check emails and watch films. Phone calls and text messages are old hat. The downside is fairly miserable battery life – 24 hours is unusual, by comparison with four or five days for a mid-market, basic handset. So a world of apps, movies and permanent connectivity is balanced by a need to charge everything more often.

Those apps, the small pieces of software you can download to augment the functions built in to a mobile phone, are also a growing and much-publicised part of mobile phones. Whether it is mobile gaming using Facebook or getting the cheapest deals on shopping, they can make enormous differences. eBay’s new app, for instance, allows you to scan any bar code and then see if it is available cheaper on the site’s global marketplace. Such technology unleashes new economic possibilities that simply did not exist until recently.

In many ways, which phone you buy now comes down to how much you want to pay for image. Judging by the fact that three-quarters of iPhone 4 orders were from people who owned iPhones already, loyalty and image are powerful forces when it comes to mobile phones.

These are devices many people now believe speak volumes about who they are as individuals, and they’re prepared to pay significant amounts of money.

Networks are also becoming a more important part of the jigsaw: as more phones use more data, the price that is charged to access the web and email is becoming more important.

If there’s a conclusion, however, it’s a hopeful one: as phones become more like mini computers, they’re becoming more and more upgradeable. So among the best Android phones on the market is still the ageing Google Nexus One, because it carries the latest software.

Apple’s iPhone 3GS, too, upgrades to the iPhone 4 software and offers much of the same functionality. These two companies make the crucial elements to new phones: the interface.

So as we all use our phones to run aspects of our daily life, what matters more and more is the ability to keep pace. Only Google and Apple currently offer that.