HTC, it was long rumored, was working on a large smartphone with full-HD 1080p display, and finally the rumors have come true.

The Taiwanese mobile major unveiled its Japan-bound J Butterfly in Tokyo on Wednesday, Oct. 17. The phone packs a 5-inch Super LCD3 display with 1920 X 1080 pixels resolution glowing at a pixel density of 440ppi. The device will launch on Japanese carrier AU by KDDI.

It's not only the jumbo screen; specs of the J Butterfly are also superlative. It runs on Qualcomm's APQ8064 quad-core Snapdragon S4 processor clocked at 1.5 GHz with MDM9615 baseband chip. The device has 2GB of RAM and 16GB of internal storage. It also has a memory card slot that supports microSD cards sized up to 32GB.

Connectivity options include 4G LTE, Near Field Communication (NFS), Bluetooth 4.0 and microUSB 2.0. With Wi-Fi 802.11 b/g/n, it also supports the trending 5GHz frequency band and wireless tethering for up to 8 devices.

The J Butterfly has 8-megapixel rear camera that can shoot 1080p videos. The front-facing camera in the device is 2.1-megapixel. Unfortunately, the battery is just 2,020 mAh, which is not justified for a smartphone with a huge display and offering LTE connectivity.

The device runs Android 4.1 a.k.a Jelly Bean out of the box. It will come in red, black and white, when it hits shelves in December.

HTC J Butterfly is a big-sized phone. However, when compared with the One X, it doesn't feel that big. It measures 143mm X 71mm X 9.1mm and is just 10g heavier than the HTC One X. The J Butterfly is also a rugged phone; it was awarded IPX5 certificate for its dustproof and waterproof features.

The J Butterfly is a Japan-only model, but HTC commits to release its variants featuring the same display in other countries. We expect HTC to sell similar smartphone in U.S. in the near future, possibly by mid-2013.

HTC is struggling to compete with Samsung and Apple. In the recently-ended quarter, the Taiwanese mobile maker experienced a 79 percent drop in profit, compared to the same quarter last year. Reportedly, HTC is focusing on top-notch smartphones only, and the J Butterfly looks like a good start.