Bigger devices, bigger screens and more pixels

The evolution of the smartphone display, what next?

I clearly remember my first mobile phones a Motorola, then an Ericsson and then several Nokia handsets. At that time small monochrome screens and alphanumeric keypads were standard with features like SMS, colour screens and cameras added as the available technology advanced. Any new feature that came along at the time seemed amazing just like it can today but now the technology, range and volume of products available is advancing so much more rapidly.

With earlier mobile phones the emphasis was on the word phone since that was their primary function. Today there are a lot more options available from traditional mobile phones to touch screen based smartphones ranging in size and price points. In this case I'm going to focus on large screen touch only smartphones and looking at where we seem to be heading in terms of the sheer number of physical screen sizes and display resolutions available.

I should note before I start that while I'm aware of the differences I'm not going to refer to screen technologies like AMOLED versus LCD with an RGB or PenTile matrix or viewing angles or color reproduction. I won't refer to device availability by area or region or mobile operating systems of which there are too many not too mention the individual versions of each. All are topics perhaps for other discussions.

The announcement of the first Apple iPhone in 2007 revolutionised the mobile products industry. There had of course been touch screen phones available before the first iPhone which at launch didn't even support 3G data but it was the combination of a glass touch screen with a touch-optimised operating system supporting multi-touch that was the game changer.

Later in late 2008 came the HTC T-Mobile G1 running Google's new Android phone operating system and thus began the battle between Apple iOS and Google Android based smartphones and tablets that continues today. I should note that unlike the first iPhone the G1 featured a full QWERTY keyboard placed behind the display and didn't support multi-touch but as the first Android smartphone to be made commercially available it marked a turning point in the race for touch screen smartphones.

The devices featured 3.5 and 3.2-inch displays with a resolution of 480 x 320 pixels known as Half-size VGA (HVGA). Later versions of the iPhone continued with a resolution of 480 x 320 pixels until the launch in 2010 of the iPhone 4 with a display resolution of 960 x 640 pixels known as Double-size VGA (DVGA) branded by Apple as Retina Display but still at 3.5-inches.

Images from gdgt.com

As things progressed with screen sizes and the number of pixels available increasing in early 2011 came devices like the Motorola Atrix that you could connect to a laptop accessory. I recall great excitement when this product was announced as the concept appeared to have potential but it appears that for several reasons the product didn't do so well. The Atrix featured a 4-inch display with a resolution of 960 x 540 pixels referred to as quarter High-Definition (qHD) as it's exactly one quarter of a Full High-Definition (Full HD) 1080p display. I had assumed that in late 2012 qHD based displays were not so common anymore but it seems there are still some like the BLU Quattro 4.5 and LG Optimus F5 becoming available in certain markets for what are now considered lower-end devices.

Image from engadget.com

Fast forward to today, February 2013 and for smartphones the use of physically larger displays with higher resolutions and true widescreen aspect ratios are the trend. Leading this trend is Samsung with High-Definition (HD) 720p displays with a resolution of 1280 x 720 pixels with a true widescreen 16:9 aspect ratio. And supporting such high resolutions has meant bigger screens as well. Below from left-to-right the Samsung Galaxy S III with a 4.8-inch display, the Samsung Galaxy Note II with a 5.5-inch display and the Samsung Ativ S with a 4.8-inch display and all with a resolution of 720p.

Images courtesy of Samsung

Image courtesy of Samsung

In this category of 4.8-inch smartphones is another product from Samsung which is interesting in that it incorporates a display similar in size and resolution to that of the Samsung Galaxy S III and Samsung Ativ S but it's not a smartphone it's a 16.3 Megapixel camera.

In addition to the 720p displays with a resolution of 1280 x 720 pixels are displays with a resolution of 1280 x 768 pixels known as Wide XGA (WXGA). These are similar to the 720p examples but adding an additional 48 pixels to the width of the display. These displays are of course widescreen format but not with a true widescreen 16:9 aspect ratio. There are several smartphones utilising this resolution such as below from left-to-right, the Google Nexus 4 with a 4.7-inch display, the Nokia Lumia 920 with a 4.5-inch display and the more recently announced Blackberry Z10 with a 4.2-inch display.

Images from tmonews.com and courtesy of Nokia and BlackBerry

Image courtesy of Apple

And out on it's own is the latest smartphone from Apple the iPhone 5 featuring a 4-inch display with a resolution of 1136 x 640 pixels up from the 3.5-inch display of the previous iPhone 4S with a resolution of 960 x 640 known as Double-size (DVGA).

Since a 4 to 5.5-inch smartphone with a display resolution of 1280 x 720 (720p), 1280 x 768 (WXGA) or 1136 x 640 pixels is possible then perhaps a display with 6-inches or more would start to suffer in terms of pixel density or pixels per inch (ppi) a value that is commonly used in terms of evaluating the latest display technologies. Although for many consumers purchasing a new smartphone this may not be taken into consideration.

Becoming available now are Full High-Definition (Full HD) 1080p smartphone displays with a resolution of 1920 x 1080 pixels with one of the first being the HTC Droid DNA for Verizon Wireless in the North America. With a 5-inch display it was launched as "The first full HD 1080p display with the highest pixel density of any smartphone". Along with the Droid DNA a slew of 5-inch 1080p display phones have also been launched. Below from left-to-right the HTC Droid DNA, Sony Xperia Z, ZTE Grand S and Huawei Ascend D2.

Images courtesty of HTC, Sony and Huawei and from androidcentral.com

The HTC Droid DNA shown above featuring a 5-inch 1080p display with a pixel density of ~441 ppi has just been surpassed by another device also from HTC the HTC One shown below. This device will also feature a 1080p display but packed into a smaller 4.7-inch screen which the guys at theverge.com stated "at 468ppi, it's one of the most pixel-dense displays we have ever seen".

Image courtesy of HTC

To place that amount of pixels in a 4.7-inch screen is no mean feat and especially when you consider that it has the same display resolution as for example a 46-inch Full HD 1080p TV.

Images courtesy of HTC and from gizmodo.com

At this point we're reached a smartphone with a resolution of Full HD 1080p display squeezed into a 4.7-inch display. I guess market forces will dictate which physical screen size and display resolution combinations works best. The Samsung Galaxy S III with its 4.8-inch display and a resolution of 720p has been a very successful product
and one assumes that any successor to that device will feature a 4.8 to 5-inch screen with a resolution of 1080p. The successor to the Samsung Galaxy S III is the Samsung Galaxy S4 which indeed ships with a 5-inch 1080p display.

Image courtesy of LG

Another smartphone with a 1080p display is the LG Optimus G Pro but with a larger 5.5-inch screen similar to that of Samsung's Galaxy Note II but not in resolution since the latter features a 720p display. theverge.com notes "At 400 ppi, the new Optimus G Pro's display is far sharper than 720p screens even on much smaller phones" and "the resolution advantage really makes itself felt at larger screen sizes — the 5.5-inch, 720p Galaxy Note 2 felt like it was stretching its pixels a little thin". So it seems that for screens of 4.7 to 5-inches a resolution of 1080p will become standard and if bigger at 5.5 to 6.5-inches then a similar resolution would be optimal.

Image courtesy of Huawei

There doesn't seem to be hard and fast rule on what resolution is required for a certain screen size when you consider for example the Huawei Ascend D2 with a 5-inch 1080p display and from the same manufacturer pictured on the right the Ascend Mate with a 6.1-inch 720p display. And the ZTE Grand S featuring again a 5-inch 1080p display and the ZTE Grand Memo with a 5.7-inch 720p display.

I think that for many consumers looking at a new smartphone with a display of 5 to 6-inches or more in size and a resolution of 720p that the pixel density or resolution will not be a deciding factor but rather the physical size of the device. Many consider smartphones such as the Samsung Galaxy Note II with a 5.5-inch screen just too big and closer to a tablet in size thus creating a new device category of phablets or tablet phones. The video below from theverge.com shows the Huawei Ascend Mate with its 6.1-inch 720p display and in this case I think the reference to it being "pretty colossal" is an apt description.

And in addition a video below from pocketnow.com comparing the 6.1-inch Huawei Ascend Mate with with the 4.8-inch Samsung Galaxy Note II both with 720p displays.

It seems there's a rumoured 6.44-inch 1080p device coming from Sony so smartphones may become even bigger. But at least it has a higher resolution display...
Update: Sony did indeed announce that device in late June, the Sony Xperia Z Ultra

You may notice in the video above from pocketnow.com a reference to the use of screen real estate for buttons which in terms of how larger screens are being used in smartphones is the only functional aspect I wanted to note here. That is the placing of buttons for commonly used functions like back, home or multitasking either virtually on the screen itself referred to as software buttons or on the device just below the screen and referred to as soft buttons. The placement and arrangement of these buttons varies by device and manufacturer and in particular for Google Android based devices.

The Google Nexus 4 shown below features software keys which as you rotate the device from portrait to landscape also rotate and can be hidden for those cases where they're not needed for example in the camera application or when playing a game.

Images from tmonews.com and guardian.co.uk

Of course the use of software keys requires additional screen space but I think there's a lot to be said for hiding these buttons. For example a classic demo effect where you give your phone to a friend who accidentally touches a soft key below the display which takes them out of what it was you wanted to show them.

Mobile World Congress 2013 in Barcelona promises more smartphones with more to follow. I'm not sure where the smartphone display can go next. One would assume that with a resolution of 1920 x 1080 pixels (1080p) in a smartphone display 4 to 6-inches in size we've reached the zenith of what's possible or dare I say acceptable in a device that should also function as a phone and as something that's with you most of the time.

I assume that nobody will try and place an Ultra High Definition (UHD) resolution display at for example 3840 x 2160 pixels (4K UHD, 2160p) into a 5 or 6-inch smartphone screen assuming of course that would be technically possible. Or at least not until 4K TVs along with content to support them become common place. What do you think?

Update: Samsung have anounced the new Galaxy Note 8.0 with an 8-inch display with a resolution of 1280 x 768 pixels which is part of the Wide XGA (WXGA) set of resolution sreferred to above. While this device isn't interesting from the point of view of it's display resolution given that at 189 ppi it's stretching things a little it seems Samsung will make available an international version which can be used to make calls but I assume this will not be sold as a smartphone. Anyway interesting so take a look at the video from theverge.com below.

Update: Samsung have announced some more big screen devices. This time the Samsung Galaxy Mega 5.8 with a 5.8-inch 960 x 540 pixels (190 ppi) qHD display at which as noted above I assumed were not so common anymore and the Samsung Galaxy Mega 6.3 with a 6.3-inch 720p display (~233 ppi). These are not high-end so they should come cheaper than the Samsung Galaxy Note II and new Samsung Galaxy S4?

And a review of the Samsung Galaxy Mega 6.3 by Steve Litchfield, a Blogger based in the UK.