Why an iPad HD?
The rumour mill has gone back into overdrive with the possibility of an iPad HD coming this september. To be specific an iPad 2 resolution doubled in both dimensions, transforming the 1024x768 screen to 2048x1536.
Why not just plain old HD?
There are a lot of industry pundits going on about the iPad moving to a traditional HD resolution (1920x1080), but we’ve already seen Apple’s approach to handling this kind of issue with the iPhone 4.
Leaving aside the Retina display designation, the simplicity of doubling the resolution (or quadrupling for the math purists), the entire object of maintaining the aspect ratio is that the entire application library will keep working exactly as before, requiring absolutely no rewrites from the developers on day 1. Any screen objects that are drawn dynamically from objects (most notably text) will immediately be displayed at the full detail of the screen. Bitmaps can be updated later on to profit from the additional visual detail, but are not required on day 1. Not to mention that the SDK already knows how to handle this so developers have a proven roadmap to update their applications
Changing the aspect ratio means that all of the detailed design work done in existing applications will need to be revisited and updated in order to match the new resolution. Apple just isn’t going to do this to their users or their developers.
Scaling to anything other than a whole number is just not going to work
Why not now?
As mentioned by John Gruber in the earlier link, there are few things that will pose issues: memory, the graphics card and battery life. 2048x1536 is an awful lot of pixels to drive, especially on a mobile device. Ensuring that the machine is capable of maintaining the fluidity of the user experience while handling the equivalent of a 30" desktop display is a non-trivial engineering feat. Adding in the fact that this needs to be done off a battery makes it even more difficult. Doing this at a cost that remains reasonable - I’m guessing about a $200 premium over the existing iPad 2 - adds to the challenge.
All of the above noted, if there’s anyone with the necessary engineering experience and expertise right now, it’s Apple.
Is it needed?
Apple is clearly doing just fine with the current iteration of the iPad and adding a new model doesn’t seem to make any sense, especially given that the competition clearly has a way to go before they start representing any kind of threat to the iPad 2. An iPad 2 HD isn’t going to grow the market any faster than the current one since it will be appealing to a higher-end niche market. Thought of the day - what if it ships with Final Cut Pro X for iPad?
But this is the opportunity to hammer another nail in the coffin of the competition with a model that nobody else will be able to touch. Currently Apple is the only player with the pockets deep enough to invest in volume production of this type of screen since they’re the only ones that can pretty much guarantee the return on investment. This ties in nicely with Horace Dedius’s observation in a recent podcast quoted by Phillip Elmer DeWitt over at Fortune
When tech journals to do their reviews of competing products and they come down the inevitable iPad comparison, there will always be that last reference to the fact that the iPad 2 HD is out there that represents the next level up. Even if it’s more expensive, the simple fact that it exists will diminish the interest in other products.
Is it realistic to expect?
I really don’t know. If I were asked is it possible, I’d say yes with the caveat that it would probably have to be about as thick as the original iPad if it’s going to be able to maintain the same level of autonomy. But after that it’s impossible to tell from the outside of Apple.