Recently, Sony announced that the Android 6.0 Marshmallow update for Xperia Z5 series, Xperia Z4 Tablet and Xperia Z3+ devices will be rolled out shortly. Following the announcement, some Xperia Z5 and Z5 Compact device owners have already started receiving the software update. The bigger Sony Xperia Z5 Premium with 4K display is expected to receive the firmware soon.

In the meantime, Xperia Blog said the company has apparently rolled out the firmware to Sony Zperia Z3, Xperia Z3 Compact and Xperia Z2 to selected beta testers. To be specific, Sony is seeding the “Android 6.0.1” build for the aforementioned devices.

Similar to other beta builds, this update has been made available only to the Xperia beta program participants. The beta testing has apparently been going on for some time now and these are countries participating in this test — Sweden, Denmark, Norway, Finland, Iceland, Estonia, Latvia, Lithuania, United Kingdom, Ireland and Germany.

After installing the beta update, Sony devices should show the following build number: 23.5.A.0.486. The Android 6.0.1 contains all the Marshmallow goodness along with security patches up until December 2015. However, it does not have the latest security patch dated February 2016.

According to GSM Arena, these are early builds and the target audience is beta testers. Not to forget, there are many old Xperia devices eligible to get the Marshmallow update. This is the reason for the extensive testing prior to rolling out the update to general public.

Apart from the new features that come with Android M like Doze to save battery life and changes to runtime app permissions, the new Xperia software also brings in camera app enhancements and the new Xperia Launcher.