Sony only recently announced the Xperia Z1 Compact at CES 2014, but rather than a replacement for the Z1, it is a compact version of the device, with another new handset rumoured to be joining the company's line up as a successor.
The new device - expected to be the company's next flagship model - has had a number of names associated with it including Sony Sirius, the model number D6503, and Sony Xperia Z2. The Xperia Z2 name is really just an assumption, as we wait for Sony to officially announce the new handset.
We've rounded up the rumours and speculation to draw up a picture of what we might expect from Sony's next flagship Android handset. We will be regularly updating this feature as more details surface, so keep checking back.
Sony Xperia Z2 release date
In the past Sony has released two flagship devices a year and we suspect 2014 will be no different. The Xperia Z1 was announced at IFA in September 2013 and rumours suggest its successor will be announced at Mobile World Congress in February 2014.
An MWC release hasn't been confirmed by Sony, but the company has used the event as a platform for big launches previously, as well as CES in January. As CES has come and gone - without a new flagship launch - we'd expect that MWC is in Sony's sights.
Sony Xperia Z2 display
The Sony Xperia Z2 was initially said to be coming with a 5.2-inch display, featuring a 2560 x 1440 pixel resolution, which would make it one of the sharpest displays on the smartphone market. That may be nothing more than a fantasy, however, with more recent hardware records from the D6503 reporting a regular 1920 x 1080 pixel display.
The size from more recent leaks sticks at 5.2-inches giving it a pixel density 424ppi, the same as the LG G2. Screenshots from the device report a resolution of 1776 x 1080, with 144 lines being given over to the touch panel across the bottom of the display.
You can expect plenty of talk of Triluminos and X-Reality Bravia technology come launch day.
Sony Xperia Z2 design
Given the praise Sony has received for the design of its Xperia range, we suspect the next flagship will follow a similar path to keep it in line with the Xperia Z family. It has been suggested the new device will be slimmer than its predecessor and come with the water-resistance feature, which we think is likely.
Hopefully Sony will also introduce a thinner bezel, similar to the approach taken by LG with the LG G2, as the Xperia Z1 was criticised for its large bezel.
More recently some images have appeared online of the Sony D6503. The images present a device with a similar look to the Xperia Z1 but with thinner side bezels, along with three microphone holes at the bottom, a Micro-USB slot, SIM tray and a microSD slot.
Other features such as the power and volume buttons, as well as the camera button, look the same as the Xperia Z1.
There's a small detail you can pick out, which is dual front-facing speakers. This should give audio a nice boost, but whether it will be a capable as the BoomSound speakers on the HTC One remains to be seen.
However, it appears that the Sony Sirius isn't going to be slimming down and may in fact be slightly taller than the Z1, if a photo appearing on Digi-wo is authentic.
Sony Xperia Z2 processor, battery and connectivity
The Sony Xperia Z2 has been rumoured to be coming with a 2.3GHz quad-core Qualcomm Snapdragon 800 processor, which would be the same as the current Xperia Z1. There could possibly be a jump up to 3GB of RAM, matching the Samsung Galaxy Note 3, which should make for a speedy device.
There have been questions raised about why the Snapdragon 805 chipset isn't being used. Although Qualcomm said to expect devices on the new hardware in the first half of 2014, it's believed that there hasn't been enough time for device manufacturers to integrate the hardware for the immediate launch cycle.
While the processor may not see a step up, AndroidSaS reported the Sony Xperia Z1 will feature a 3700mAh battery. We're certain the battery will be a focus for Sirius and Sony's Stamina mode and granular power controls should keep things going through the day.
As expected 4G LTE connectivity is also rumoured, but that is pretty much a given as it is a high-end device and its predecessor comes with it.
Sony Sirius user interface
More recently we've seen an extensive leak from what purports to be the Sirius, revealing much of what Android 4.4 KitKat will offer on the device, along with the normal Sony additions.
The Xperia Z2 incorporates some of KitKat's native features - like support for multiple launchers - but offering the normal Xperia home as well as a simple home. The latter offers larger icons and fonts for those who want a fuss-free experience.
Although the look and feel appears to be much the same as other devices in the Xperia line of Android handsets, there are some notable additions revealed in the software leak. There's a new tab for managing power of accessories - we assume for the likes of the Sony SmartBand.
There is mention of High-Resolution Audio, as well as some smart gesture controls - similar to those used by Samsung - for example answering a call by lifting the phone to your head, or keeping the screen awake when you're looking at it.
There's also a new app called What's New. It's not exactly clear what it's for, but it's accessed in a similar way to Google Now. The leaked images show it full of Sony Entertainment Network content, we're hoping it's more ambitious than just a method of pushing Sony's movies and music.
More recently we've seen a brief video showing some of the basic features, but not exploring any of the hardware on offer.
Sony Xperia Z2 camera
The camera on the Xperia Z1 was one of its most talked about features and the next flagship is rumoured to be coming with the same 20.7-megapixel offering.
The leaked screenshots reveal a 4K capture option, but that really shouldn't be a surprise. That was a feature of the Galaxy Note 3 in 2013 and it makes sense for companies like Sony and Samsung to really push 4K, as they have a 4K ecosystem to populate. There's also a slow motion option, which we hope will work like that of the iPhone 5S.
There's been a flood of information surrounding Sony's Sirius device and we expect that to continue up till launch day. We will continue to update this feature as more information gets uncovered, so be sure to check back!