Putting a camera on a mobile phone was the best idea since piping icing onto a cake. Nowadays, more photos are taken on mobiles than all the stand-alone cameras in the world put together -- but the sad truth is that a lot of them are still blurred, dull and grainy.
It's hardly surprising. Most phone cameras sport a lens the size of a drawing pin and photo modes that have more in common with the original Box Brownie than today's digital SLRs. But there are some excellent exceptions, and finding them is easy if you know what to look for.
Although resolution isn't the be-all and end-all of digital photography, it indicates how seriously a phone maker takes imaging. Mobiles with a 5-megapixel resolution or higher tend to have more and better features than their low-res brethren. These produce pictures big enough to print at up to A4 in size -- that's plenty for a mobile snap. But don't think that more megapixels is always better.
Jumping up to 8 or 10 megapixels can increase digital 'noise' without visibly improving detail. Factors such as the quality of the lens and size of the sensor will then determine whether you get awesome or awful shots.
HTC took a bold move in plonking only a 4-megapixel snapper onto its flagship phone. It claims, however, that the individual pixels are bigger, resulting in better image quality overall. That might sound like marketing nonsense, but I can't deny I was impressed with the images.
Auto-focusing is an absolute must. Look out for a macro mode for really sharp close-ups. Some camera phones come with all manner of specialist scene modes but, honestly, how often will you really select 'food' or 'museum' mode before hitting the shutter? More useful are easy, one-touch overrides such as exposure compensation for highlights or shadows, and spot-focusing to concentrate on your main subject.
The other essential is an LED -- or, preferably, a xenon -- flash. LED lights are fine for illuminating a single person or nearby object but a proper xenon flash, like the ones found on dedicated cameras, will punch out enough photons to light up an entire room. Be warned, though: these can really munch through your battery.
Other features worth looking out for are face detection, intelligent exposure, high dynamic range, automatic panoramas, 'smile shutters' and burst modes. You might not find yourself using them often, but they're likely to come in handy.
If you want a seemingly endless set of features and camera tricks, check out the Galaxy S4. Its vast selection of camera additions, while not exactly crucial to the phone, will certainly help you create some wacky shots to jazz up your Facebook page.
Some of these features can be neat, but there's something to be said for simplicity too -- just having lots of features and options doesn't make a camera phone great. In some cases, quite the opposite. Some of the best camera phones -- such as the iPhone 5, which has a paltry set of shooting options -- are able to strip away unnecessary complexity and zero in on producing reliable results in a variety of conditions.
When it comes to screens, quality is more important than raw size. Look for displays of 4 inches or more, so you can comfortably compose your shots without the camera software or your fingers getting in the way. The higher the screen resolution the better too -- to give you the best chance of determining whether the shot you just snapped was in focus or not.
Storage is another consideration -- some phones offer a microSD card slot so you can easily expand the amount of space you have to save your shots. Smart phones can also be set up to automatically upload photos to cloud storage or social networks such as Dropbox or Google+ -- a handy way to keep snaps backed up.
Phones with built-in GPS should automatically geo-tag your photos with their location, and of course there are bags of photography-related apps to fill any feature gaps. There are apps out there to stitch together panoramas, add visual effects, edit your photos on your mobile and even replicate old-style film cameras. Apple's iOS and Google's Android both offer an extensive collection of apps to augment your camera experience.
If you plan on editing all your snaps before sending them off to your Twitter followers, you'll find a speedier phone -- with a dual- or quad-core processor -- better for you. You'll spend less time waiting for filters to apply and your phone is less likely to become overwhelmed and force-close the app.
Focus in on the latest camera phones with CNET UK reviews -- here are a handful of the best to get you started, in no particular order.
You should also have a gander at our comparison tests for some excellent examples of these phones' pics. Here's how the Galaxy S4 stacks up against the HTC One, iPhone 5, Xperia Z and Lumia 920. We've also tested how the iPhone 5 compares to the Samsung Galaxy S3 and HTC One X, and how today's best camera phones measure up to the innovative Samsung Galaxy Camera.
Additional writing by Mark Harris and Natasha Lomas.