We handled an awful lot of devices in 2013 and were impressed with the innovative imaging features and technologies we saw. But some smartphones truly stood out from the rest.

2013 has been an exciting year for mobile imaging with lots of new features and technologies, as we've been covering here on DPReview Connect. We've seen innovations in sensors, new software features and a general tendency to focus on the imaging capabilities of mobile devices. As we reflect back on the past year and look forward to even more interesting advances in 2014, we're sharing our thoughts on the most important trends in smartphone imaging in 2013. 

Bigger sensors

Despite the fact that these days far more images are captured with mobile devices than dedicated digital cameras, for a very long time smartphone users have had to make do with the smallest image sensors on offer. The tiny 1/3-inch or even 1/3.2-inch sensors that have been the standard in smartphones for many years are smaller than the chips in even basic compact cameras and in general produce inferior image quality.

Launched in February 2012 the Nokia 808 PureView was the first smartphone with a larger sensor. Its 1/1.2-inch sensor is almost the same size as the 1-inch chips you would find in a Sony RX100II enthusiast compact or Nikon's 1 system cameras. But the device launched running the already outdated Symbian operating system and the 808 never stood a chance in the marketplace, despite the outstanding image quality of its camera.

This diagram illustrates different sensor sizes. The Sony Xperia Z1's is quite a bit larger than the standard 1/3-inch smartphone sensors but not anywhere near the Nokia Lumia 1020's 1/1.5-inch sensor. 

In 2013 Nokia finally combined the 808's innovative imaging concept with a modern OS and launched the Lumia 1020 Windows Phone. Its 1/1.5-inch sensor is not quite as large as the 808's, but the camera applies the same concept. The sensor captures very high resolution images that are then downsampled to output a high-quality 5MP image. The same technology also allows for a much better than usual digital zoom. The full 41MP files remain accessible to those who want to use them.

The Sony Xperia Z1 is the second smartphone with a larger than usual imaging sensor that was launched in 2013. Its 1/2.3-inch sensor is nowhere as extreme as the Nokia's, but it is the same size as sensors found in consumer level compact cameras. The improvement in image quality over the typical smaller sensors is much less noticeable on the Sony than it is on the Lumia 1020 but nevertheless it's good to see that manufacturers are working to make larger sensors fit and work in thin smartphone bodies. 

Nokia's brand new 6-inch "phablet" Lumia 1520 which combines a 1/2.5-inch 20MP sensor with PureView technology is the latest model to implement a sensor that is larger than what has been the standard so far. We'll have to see what sensor sizes manufacturers will pull out of their sleeves in 2014 but there is no doubt that we can expect more larger sensors in the next generation of devices.  

Optical Image Stabilization

Optical Image Stabilization systems have been around in digital cameras for a long time and have helped photographers capture blur-free images at slow shutter speeds and smooth video footage, either by moving the image sensor or an optical element of the lens in order to counteract camera shake. 

However, it's taken a while for this feature to trickle through to smartphone cameras. With the Lumia 920 Nokia was the first manufacturer to offer OIS in a smartphone in late 2012 and since then all high-end Nokias have come with the feature, including the latest flagship Lumia 1020. 

Moving lens elements in Nokia's Lumia phones, the HTC One, LG G2 and Google Nexus 5 keep things steady when the shutter speeds get slow or when shooting video.

In 2013 OIS has become something of a mainstream feature, with several top-end Android phones, such as the HTC One, LG G2 and Google Nexus 5, jumping on the bandwagon. Apple users currently still have to make do without OIS, but there is not doubt that it's a useful feature that can help improve your images in certain situations and we would not be surprised if it was implemented into the next generation iPhone. 

Bigger screens with more pixels

It started with the Sony Xperia Z, revealed at the Consumer Electronics Show in Las Vegas, Nevada at the beginning of January, which was the first mainstream phone to be launched with a 5-inch screen and 1920 x 1080 pixel full-HD resolution. After the Sony's debut, other top-of-the-line Android smartphones, such as the HTC One, Samsung Galaxy S4 and Google Nexus 5, have all been launched with the same display specs. LG's G2 comes with the same resolution but a slightly larger 5.2-inch display.

The thinner bezels on those latest generation devices mean that the overall dimensions of the phones aren't any larger than the 2012 models with their 4.7 or 4.8-inch screens and 720p resolutions.

The Sony Xperia Z was announced at CES 2013 and the first device by a large manufacturer to come with a 5-inch 1080p screen. Virtually every top-end phone announced after the Sony offered the same size specs.

Outside the Android world things look a little different though. Apple didn't adjust the iPhone 5's 4-inch screen size or 1136 x 640 screen resolution when it launched the 5s and Nokia has stuck with 4.5-inch 720p screens on its smartphones for a while now.

That said, there are never-ending rumors that Apple will launch an iPhone with a larger screen and Nokia just came through with the Lumia 1520 "phablet" with a 6-inch 1080p screen. Realistically though it is hard to see how even higher resolutions on 4 -or 5-inch screen make ergonomic sense. There is no doubt we will see more innovation in the screen department in 2014, but we would expect the focus not to be only on pixels but also viewing angles and color reproduction. And of course there will be more curved screens

Phablets 

Phablets, as smartphones with screens larger than 5-inches are commonly called, are definitely here to stay. When Samsung launched the original Galaxy Note in 2012 there was some doubt about whether the unusual dimensions would catch on with consumers, but in 2013 these devices carved out a fairly large niche for themselves.

Samsung's Galaxy Note III on the left is one of the most popular "phablets" around and replaces the Note II on the right. 

The third and current generation of the Note has been one of the hottest devices of the year and virtually every manufacturer offers at least one 5-inch-plus device in their line-up. HTC launched an oversized version of its flagship model One, the One Max, and Nokia's brand new 6-inch 1520 comes with a 20MP 1/2.5-inch sensor that we are keen to get our hands on. 

Camera App Features

Smartphone manufacturers not only showed us some innovative camera hardware in 2013 but also released a slew of software features. New functions included 360 degree panoramas, composite images, picture-in-picture effects using the front and rear cameras at the same time, the removal of unwanted subjects in your frame, animated GIFs and the ability to refocus images after they've been taken.

New software features reach from fairly useful like the Samsung Galaxy S4's Eraser mode ...
... to gimmicky, like the Sony Xperia Z1's Virtual Reality mode.

In addition to those new features existing ones were improved, with panorama modes capturing much bigger images and HDR functions producing more balanced results and dealing better with moving subjects in the frame. While some of those features are genuinely useful others are firmly based in the gimmick camp.

We have no doubt that device manufacturers will surprise us with all sorts of useful and not-so-useful new functions in their camera apps in 2014, but the beauty of using a smartphone for taking pictures is that you've got access to an abundance of apps. So, if you are contemplating a device that does not offer one or another software feature there is a good chance you'll find a third-party solution in the app store of your choice. 

4K video

4K TV sets are the latest big thing in display technology. The high-resolution screens were omni-present at this year's consumer electronics trade shows and are by now widely available in retail stores too. Unfortunately there is not a whole lot of 4K content available at this point in time which is why it only makes sense that manufacturers are starting to implement 4K capturing capabilities into their devices.

The Acer Liquid S2 and the Galaxy Note III were both launched at IFA in Berlin and are the first smartphones to offer 4K video recording.
This frame grab from a Galaxy Note III 4K video shows noticeably more detail than a 1080p equivalent.

The Acer Liquid S2 and the Samsung Galaxy Note III were the first two smartphones launched in 2013 that can capture 4K video footage but as the displays become more affordable there is no doubt that 4K capturing will catch on in both digital cameras and smartphones. Expect to see many more 4K-capable devices in 2014.

RAW Capture

A lack of RAW capturing capability is an often-cited reason enthusiast photographers say they won't shoot with smartphones. However, there are a lot of signs on the horizon that this is about to change. Nokia's 1520 "phablet" was the first smart device that is capable of saving DNG RAW files from its 20MP CMOS sensor and a firmware update recently added this feature to Nokia's flagship smartphone, the Lumia 1020, too.

You can now edit DNG files from both the Nokia Lumia 1520 and Lumia 1020 in Adobe ACR.  We should also see the first Android phones with RAW capturing in 2014.

But soon it won't only be Windows Phone users who can play with their images in Adobe ACR or other Raw editors — Google also announced the implementation of RAW capturing capabilities in future versions of Android. We'll be interested to see how that pans out with so much variation in Android hardware but nonetheless it seems RAW capture is about to become a standard feature, at least on high-end devices, and we are looking forward to modifying the white balance or reducing noise reduction on some of our smartphone pictures in the near future.