According to Apple, a display deserves the Retina moniker if its pixel density is so high that your eye is unable to discern the individual pixels. In the case of a smartphone, Retina means at least 300 pixels per inch. The Retina display on the iPhone 4/4S/5 has 326 pixels per inch.

Now, imagine a five-inch phone that packs 440 pixels per square inch, featuring the native full HD resolution of 1,920-by-1,080 pixels. That’s exactly what the ailing handset maker HTC set out to create with a new upcoming phone dubbed the J Butterfly…

Apple’s Retina display has served as one of the defining hardware features of iPhones since the iPhone 4. Even a year after the iPhone 4 had been released in the summer of 2010, competition had trouble producing a matching display.

But increasingly pixel density is becoming a weapon against Apple and this new HTC phone is a typical example.

The Verge had a chance to play with HTC’s new phone in Tokyo today.

The J Butterfly features a five-inch Super LCD 3 display, a successor to the Super LCD 2 screen on the HTC One X. At 440 ppi, vivid color reproduction and the slightly curved edges, this phone sets a new bar in terms of clarity and display quality.

Other features include a quad-core 1.5GHz Snapdragon S4 Pro APQ8064 processor, 2GB of RAM, an eight-megapixel camera with an f/2.0 lens, Android 4.1 Jelly Bean and a body that’s just 9.1mm thin.

It’s not that Apple is too obsessed with smartphone screen sizes or resolution, but evidently it’s been featuring the Retina display prominently in advertising.

A full HD display like that on the J Butterfly give you native 1080p video playback without letterboxing or downsampling. Here’s a comparison of the HTC phone’s display versus the iPhone’s Retina display.

So, when’s Apple gonna do a 1080p iPhone?

The technology obviously exists though yield rates and production volume of such a high-resolution mobile display may not at this point satisfy Apple’s insatiable appetite.

Other concerns involve hardware requirements and battery consumption because a 1080p display has 2.85 times more pixels than the iPhone 5’s 1,136-by-640 display, requiring a much more powerful GPU to drive the pixels.

On the other hand, president and CEO of DisplayMate Dr. Raymond Soneira tells ArsTechnica that smartphones with 1080p resolutions won’t neccessarily look any better than 720p displays.

Certainly Apple must be thinking about a 1080p iPhone and I think it won’t be too long before we get there.

What do you think?