According to Apple, the new iPad HD has a million more pixels than HDTV. The new tablet has a super-sharp 2048 x 1536 pixel Retina display. With a screen resolution so high that it might cause problems. It means that from here on out, most apps will be designed, keeping this resolution in mind and have difficulty running on any hardware that isn’t the newest model since every pixel requires a certain amount of processing power to render.
Depending on how an app was designed and developed, updating for an iPad 3 Retina display could take a long time. An app would require updating with assets that match the pixel density of the new IPAD. Without it, the apps would be rendering 1024×768 assets on an extremely high density screen resulting in washed out blocky images and details.
A regular graphic would simply be rendered with four pixels per point on a Retina display, unless proper Retina (2x) resources are in place to take advantage of the higher density for designs using entirely custom elements, every single part of the user interface needs two images created — one for the previous, non-Retina size, and another at the new, double resolution Retina size.
However, if a $50 DVD player can upscale 480p images to 1080 then Apple should be able to take 768 to 1536, right? Well if you use apple’s inbuilt elements; proprietary tools then apple should handle it. However, up-scaling is a poor substitute for native resolution.
The new iPad has a new heavy duty processor built to withstand the new rigors required to calculate so many pixels.. Code will have to be rewritten to take advantage of the new quad-core graphics module inside the new A5X processor. There might be changes in the way some of the tasks and graphics rendering is done and this might change how the tasks are allocated across the new computing mechanism. Old apps will still be optimized for the old ipad’s simpler graphics modules. Although, it’s possible that it won’t affect anything at all if Apple has taken this into consideration.