## Wednesday, December 22, 2010

### Is it really 10 inches ?

Actually the measurements in question are 9.7 and 10.1 which are the respective screen sizes, in inches, of an iPad and my Asus EeePC . And it is screen size, or how screen sizes are measured, that I'm talking about.

If you remember the rules about squaws on hippopotamuses, we can work out the actual width and height of the screens, but crucially only if we know their ratio. The iPad has a 9.7 inch diagonal screen at a 1024 x 768 ratio (often stated as 4:3 but I'll go with the numerical value of 1.33). My EeePC has a 10.1 inch diagonal screen with an odd 1024 x 600 ratio. That equates to a 1.7 ratio (somewhere between a 16:10 and a 16:9).

This gives the EeePC a size of 8.72 x 5.1 and the iPad 7.75 x 5.83. The squarer size means the iPad is actually about 2% larger in area than the EeePC despite the iPad having the smaller diagonal measure.

Thanks to silisoftware for supporting those calculations.

So a couple of observations.

Firstly, as a media consumption device, the iPad has not been optimized for widescreen movies but more for 'page' sized content. Steve Jobs is a smart guy, especially on user experience. He didn't make that choice by flipping a coin. My bet is he wasn't working out what people would use the device for either. He decides what he is going to sell, and people decide whether to buy it or not, and he wanted a portable device not a encumberance.

Secondly the size of the iPad screen includes the 'keyboard'. Googling "ipad virtual keyboard" images, it looks like the keyboard takes up most of the bottom half of the screen, at least in landscape mode. Where an application requires text entry (name, email...) a 1024x768 screen on a netbook is very different to the same size screen on a tablet. And re-jigging things when it is switched between landscape and portrait is another can of worms.

The smaller the screen, the larger the impact of any virtual keyboard. You can read characters that are a lot smaller than a 'key' you press for typing.

When Cary Millsap was presenting to the Sydney Oracle Meetup last week, one of the things he said that if the same value for a measure can result from two completely different user experiences, you are measuring the wrong thing. He was speaking about how an average may mask extreme variances, but the same applies to this situation. While the screen size of a netbook and an iPad are similar, the experiences can differ considerably.

So can people stop talking about 10 inches (and that includes those people spruiking herbal products).