A couple of months ago, Sony finally announced the much anticipated Android 5.1 Lollipop update for their devices Xperia Z3, Z3 Compact and Z2 but a resource person from Sony confirmed that the consumer electronics manufacturer giant is cooking something, secretly, with regard to the firmware on top of what they had in Android 5.1 Lollipop. That being said, Sony's sneaky moves is no longer a secret.

According to AutoOmobile, the source went public and announced that the Japan based giant is currently testing the Android 5.1 firmware and looks to launch an update to the Z3, Z3 Compact and Z2 a couple weeks from now. The update is also expected to be released to the Xperia devices simultaneously.

With the update, the Xperia users, particularly the Z3, Z3 Compact and Z2, will have a better experience than what they had in the Android 5.0. In relation to the Xperia Z3 news, Motorola's Moto X Play was touted as its closest and fiercest rival in the market, NewsJs points out.

The Moto X Play is equipped with a slightly larger 5.5-inch capacitive screen compared to Z3's 5.2 inches IPS LCD screen. Moto X Play will also boast a 1080 x 1920 pixels resolution with a density of 403 pixels per inch while Z3 has 1080 x 1920 pixels and a density of 424 pixels per inch.

Under the hood, the Moto X Play looks chunkier than the Z3. The Motorola phone will have a Qualcomm Snapdragon 615 chipset, an octa core CPU comprised of four Cortex-A53 cores clocked at 1.7 GHz and four Cortex-A53 cores clocked at 1.0 GHz and an Adreno 405 GPU.

The Z3, on the other hand, is equipped with the older Qualcomm Snapdragon 801chipset, a Krait 400 CPU with four cores clocked at 2.5 GHz and an Adreno 330 GPU. Another advantage for the Moto X is its price at around $300, without contract, while the Xperia Z3 is currently priced at $470, unlocked.

Going back, the rumored 5.1 update was also reported to have a concept user interface (UI), which will be exclusive for the Sony Xperia Z3, Z3 compact, and Z2 series. Although the concept UI is still in the testing phase, it is expected to be included in the upcoming release of the firmware, in the next couple of weeks, TechIndia cited.

According to the report, Sony has started testing the concept user interface, coined 'Android Concept', last July 27 and is expected to end on September 13. The test, which is related to Sony's secret 5.1 Lollipop update, was initially launched for Xperia Z3 users in Sweden.