Sony will take center stage in one of the tech conferences slated in early 2015, as the Japanese mobile manufacturer is rumored to go all-out next year with a complete artillery of full-fledged and mid-range smartphones. It has been rumored that the company will release a full Sony Xperia Z4 line consisting of the Xperia Z4, Xperia Z4 Compact, and Xperia Z4 Ultra. Reported specs and features of the three handsets have already surfaced online. 

The Xperia Z4 will be the direct successor of the current Xperia Z3 and is predicted to have a 5.4-inch quad HD Triluminos display, Snapdragon 805 or 810 processor paired with 4 GB RAM, Sony's new 21-megapixel Exmor IMX230 camera sensor, 3.2-megapixel front-facing shooter, and a 3300 mAh battery. The smartphone will run with the latest Android 5.0 Lollipop OS. 

Sony Xperia Z4 Ultra, on the other hand, is predicted to be the company's entry to the phablet category to match Apple's iPhone 6 Plus and Samsung's Galaxy Note 4. The hybrid device is rumored to come with a thin profile, 5.9-inch qHD Triluminos display, Snapdragon 805 chipset, 4 GB of RAM, 16-megapixel rear camera, 3.2-megapixel front-facing shooter, and a 3300 mAh battery. 

Lastly, the Xperia Z4 Compact will be a slightly smaller and mediocre version of the Xperia Z4. The handset will sport a 4.7-inch screen display with 1080p full HD resolution, 64-bit Snapdragon 810 processor, 3 GB of RAM, 32 GB of internal storage with microSD slot, 20.7-megapixel primary camera and 5-megapixel front-facing camera. 

In addition, Sony is also reported to release another mid-range smartphone dubbed as Xperia E4, which is the successor of Xperia E3 that was released at the IFA 2014 event last September. According to GSM Arena, the Xperia E4 will sport a 5-inch screen panel, MediaTek's quad-core MT6582 SoC with Cortex-A7 cores clocked at 1.3GHz, and 1 GB of RAM. 

All of the aforementioned smartphones are purported to be announced either at the Consumer Electronics Show in January or at the Mobile World Congress in March. Sony has been an active participant of the two tech conferences in the past years.  

However, these are not set in stone yet as these are mere speculations. Sony has revealed nothing official as of the moment.