It is widely assumed by the media that the next iPad Mini will sport a massive 2048x1536 resolution display, not only making it a "Retina Display", but matching the screen resolution of its bigger brother.
Not so fast.
The inclusion of a 2048x1536 display would take a big bite out of Apple's profit margin, adding around 30% to the cost of building an iPad Mini according to Apple Insider. Not only is the display itself more expensive, but the next iPad Mini would need a processor as fast as the iPad 4 to run it and a bigger battery to power it.
But Apple doesn't need a 2048x1536 resolution display on the next iPad Mini. While we often talk in pixels-per-inch (PPI), the important metric for a Retina Display is actually pixels-per-degree (PPD), which includes viewing distance in the equation. This is why the iPad 4 has a Retina Display even though its 264 pixels-per-inch falls far short of the 326 PPI on the iPhone 5. Apple assumes the iPad is being held at a 15-inch viewing distance rather than the 10-inch viewing distance used for the iPhone.
What does all of this mean? Basically, Apple doesn't need to come close to that 2048x1536 screen resolution to put a "Retina Display" label on the next iPad Mini. In fact, using the 57 pixels-per-degree of the iPhone 5 as the line needed to cross, the next iPad Mini could sport a resolution of 1376x1032 and still hit that mark. And not only does the lower resolution mean a cheaper display for Apple, it also means they could get by with including a smaller battery and using the iPad 3 processor rather than the iPad 4 processor, all of which brings the cost of the iPad Mini down.
Of course, Apple doesn't need to hit the minimum. They may go with a more standardized resolution of 1600x1200, which would give the iPad Mini 253 pixels-per-inch and 66 pixels-per-degree. It would also put the iPad Mini on top of the 7-inch Kindle Fire HD and Google Nexus 7, both of which sport 1280x800 displays.
Could Apple still go with a 2048x1536 display for the next iPad Mini? Sure, but it would seem to be throwing profit into the trash for no other reason than to make life slightly easier for developers and put more pressure on Google and Amazon to match the resolution and stick at the $199 price point.