None of the devices in this shootout are good at everything. So, if you're planning to take a lot of pictures with your smartphone, you should be clear about where your priorities are. With its 13MP sensor the Samsung Galaxy S4 clearly produces most detail in good light and shows a good overall performance. In low light the S4 tends to opt for higher ISOs than the competition, but in turn that gets you faster shutter speeds and the sensor still captures more detail than the rivals. Having 13MP to start with also means that at equalized viewing sizes the Samsung's higher noise levels will be much less noticeable than at a 100% view. That is important to keep in mind considering that almost all smartphone images are reduced in size for editing and/or sharing. The Samsung's flash performance is decent too and exposure is usually spot on.

The iPhone 5 is still a good option for mobile photographers, with good detail capture and pleasant image rendition in both bright and lower light. However, we were not impressed by the blown highlights in both our sunlight and flash portraits. The Apple device also tends to select very slow shutter speeds in low light which, given the lack of an optical image stabilization system, can lead to shaky images.

The HTC One has put a lot of focus on camera performance and while it generally produces pleasant exposures, the lack of resolution in bright light might be too much for some users. That said, it did very well in capturing the highlights in our sunlight portrait.

The fast lens combined with optical image stabilization means the HTC is a good device for capturing low light scenes -- if you can live with the 4MP output. You also need to keep in mind that the slow shutter speeds in low light won't be useful for capturing moving subjects. Flash performance is definitely one of the HTC's strengths. It did well in our comparison but we've also taken a number of flash exposure while working on our upcoming full review and found its performance impressive. The HTC is arguably the best mobile device for flash photography we've seen so far.

We weren't particularly impressed by the Nokia Lumia 920's image processing in any lighting condition but, like the HTC, its fast lens and optical image stabilization mean the Lumia's strength lies in low light capture. However, some of that advantage is diminished by the Nokia's very strong noise reduction which results in very soft images. That said, like the HTC, the Nokia is a device to look at if you are taking a lot of flash images as it did very well in that comparison.

Conclusions: An Impressive OLED Display…
The Galaxy S4 continues the rapid and impressive improvement in OLED displays and technology. The first notable OLED Smartphone, the Google Nexus One, came in decidedly last place in our 2010 Smartphone Display Shoot-Out. In a span of just three years OLED display technology is now challenging the performance of the best LCDs. Each have their own particular strengths and weaknesses, but if you scan our color coordinated Comparison Table, both displays and technologies perform quite well and look quite good and comparable overall – we’ll see how they both evolve and improve in the next generation, which we consider next…

The biggest challenge for OLEDs is continuing to improve their power efficiency and full screen peak brightness. We measured an impressive 20 percent improvement in power efficacy between the Galaxy S4 and S III, and a 25 percent increase in brightness (and up to 68 percent with Automatic Brightness). If this keeps up then OLEDs may pull ahead of LCDs in brightness and power efficiency in the near future…

Of course, LCDs are not standing still either. There has been a remarkable increase in their resolution and Pixels Per Inch. IGZO and more advanced Metal Oxide backplanes will help to significantly improve their efficiency and performance. Quantum Dots should help them to efficiently enlarge their Color Gamuts to catch up with OLEDs, which is important for delivering accurate color and image contrast in high ambient lighting.

Both OLEDs and LCDs need to carefully expand their color management and color calibration. The biggest improvements for mobile displays will come from dynamically changing the display Color Gamuts and Intensity Scales to automatically compensate and correct for reflected glare and image wash out from ambient light. Which ever one succeeds is likely to win in the next generation of mobile displays…