While Sony has yet to release many details about its upcoming flagship smartphone - the Xperia Z4, numerous speculations and rumors are flooding the Internet with purported specs and other issues related to the highly-anticipated device.

Tech Radar reports that the Japan's certification agency has already passed the Xperia Z4, demonstrating that Sony has already made a lot of progress in this regard. According to GSM Arena, a number of carriers like NTT DoCoMo, KDDI and SoftBank have also approved the Xperia Z4.

Meanwhile, IB Times has reported that the upcoming smartphone will boast a metal chassis and as far as its looks are concerned, it is likely to brear resemblance to its predecessor, the Z3. According to some reports, the Xperia Z4 will have the same screen size as the Z3 - 5.2 inches. There are other reports that claim that Sony is likely to go for a comparatively bigger display for the upcoming smartphone, which may be 5.5 inches.

The IB Times report also says that the Xperia Z4 will have a Full HD Triluminos display coupled with a 2K screen resolution. On the other hand, Tech Radar speculates that the device will come with a Quad HD screen. It is expected that the Xperia Z4 will be powered by a Qualcomm Snapdragon 810 processor together with an impressive 4 GB RAM and 32 GB internal storage capacity.

As far as the device's camera is concerned, speculations are rife that it will have a 20.7-megapixel rear-facing shooter and a 5-megapixel front snapper. Other reports claim that the handset will have a 16-megapixel primary camera and a 2-megapixel secondary shooter. According to GSM Arena, Xperia Z4 is likely to come in two variants and while the model called Xperia Z4 Ultra will have the latter specs, while the other version known as the Xperia Z4 Compact will include the former specs.

There are contradictory reports regarding the battery life of the upcoming handset. While IB Times claimed that the Xperia Z4 will sport a 3420 mAh battery, GSM Arena reported that there it will come with a 3000 mAh battery and a 3500 to 4000 mAh unit.

Earlier reports said that Sony would introduce the device at the recently concluded 2015 Consumer Electronics Show (CES) in Las Vegas. As this did not happen, now there are reports that the handset will be unveiled at the Mobile World Congress in March.