Now that it's almost impossible to buy a mobile phone without a built-in camera, manufacturers are looking for the next big thing. Given the popularity of the iPod and the astounding enthusiasm for ringtones, it's hardly surprising they've decided to bring music playback to your mobile.
There are a few things to watch out for when you're shopping for a music phone. First, how are you going to get your music on to the phone? If you're planning to download tracks from your service provider, it's worth thinking about a 3G phone. If you're going to copy it across from your computer, find out how the transfer works. Do you need a cable? Is it included with the phone? Can you use Bluetooth? Can you copy the files directly to a memory card? If transferring music is too much like hard work, you'll end up listening to the same songs over and over again.
Second, how much storage space do you get? It's unusual for a phone to have more than 100MB of built-in memory. You'll need some of that for contacts, photos, games and so on, so you'll be lucky to find space for more than 15-20 songs -- so you'll want to be able to add capacity using memory cards. Third, are you stuck with the supplied headphones, or can you use your own? Many phones use proprietary connectors rather than a standard 3.5mm jack.
Fourth, consider the battery life. If you just want to listen to music while you commute, for a couple of hours each day, and you can top up the battery at either end, you should be fine. Much more than that, though, and you run the risk of cutting yourself off. You'll have a hard time explaining that you missed an important call because you'd run down the battery listening to Coldplay.