The Sony Xperia C4 and Xperia C5 Ultra smartphones, which were launched in May and August respectively last year, have started receiving their Android 5.1 Lollipop update. Both smartphones until now ran Android 5.0 Lollipop out-of-the-box. The update is also available for the dual-SIM versions of the smartphones.
It is worth mentioning that since the updates are heavy, Sony recommends users to download them over Wi-Fi. The two smartphones can also be updated manually via the Sony PC Companion tool. Users can check for OTA updates by navigating to Settings> About Phone> Software update.
The Android 5.1 Lollipop update started rolling out in March last year, starting with Nexus devices. The OS version brings stability and performance improvements. With the new OS version, Google added new features such as support for multiple SIM cards, Device Protection and HD voice on compatible devices.
Another highlight is built-in Device Protection, which makes sure the device is locked when lost or stolen, until signed-in using a Google account. The Android 5.1 Lollipop update also brings high definition voice calling on the mobile phone. The HD voice calling will be available only on compatible Android 5.1 devices. Other features include ability to join Wi-Fi networks and Bluetooth paired device option directly available from Quick Settings.
The latest OS version Google has made available to OEMs is Android 6.0.1 Marshmallow, and few manufacturers have started rolling out that update to users of their smartphones. The OS version brings support for the new set of emojis and can be used on Google's Keyboard app that ships with the Nexus devices. It adds new emoji characters with full support for Unicode 7.0 and 8.0 emojis.