Get ready to experience the newest operating software from Google. Last year, Android 6.0 Marshmallow (also known as Android M) rolled out on Nexus devices, so the question is why the update hasn't come on other gadgets like Samsung, Motorola, HTC and LG. Sony's Xperia series have become one of the most favorite devices in the market, and Xperia users are asking when they will get Android M.

Sony is known for being is slow when it comes to Android system upgrades. The phone manufacturer is reportedly making several improvements in the OS to become compatible with their devices.

When phone manufacturers release new updates on their devices, the newest gadgets usually get the most recent version of Android operating system. Tech experts said it safe to assume that Sony Z5, the Z5 Premium, and the Z5 Compact will have Android M first before the older phone models.

However, in some cases, phone models that are released four years ago might not receive new Android system.

2015 Sony devices--the Xperia C5 Ultra, the Xperia C4, Sony Xperia Z3+/Z4, the Xperia M5, the Xperia M4 Aqua, and Sony Xperia Z4 Tablet-- are expected to have Marshmallow update.

According to Know Your Mobile, Sony will update all Z5 devices to Marshmallow this month of January. For other gadgets, they might get Android 6 from their respective carriers like Verizon, US Cellular, Sprint, AT&T, and T-Mobile.

Sony Xperia Z5 Compact, the lite version of the Xperia Z5, will be become available for the price of $499 through Amazon, Best Buy and B&H. Expect it to become available in online retailers starting Feb. 7. The Z5 Compact houses a 4.6-inch HD display along with 2 GB of RAM and 2700 mAh battery.

The other Xperia Z5 lineup boasts 5.2-inch full HD display along with 3 GB of RAM. Its battery capacity is packed with 2900 mAh power.

Meanwhile, Sony has announced that more than 10,000 Xperia Z3 and Xperia Z3 Compact owners can upgrade to Marshmallow by registering in the firm's test program; Concept For Android: Marshmallow.

For interested Z3 users, they can sign-up via Sony's official application, but these application venues are expected to vanish quickly. Z3 users from Sweden, Denmark, Latvia, Lithuania, United Kingdom, Norway, Finland, Iceland, Estonia, Ireland and Germany can participate in the program. Selected applicants will be notified in the coming weeks.