A source said that Google will launch Android 5.1 in February 2015, which is fast enough. Android 5.1 has a large number of new functions in addition to the significantly improved version number. In Android 5.1, the mute function will be added to improve battery life, system stability, RAM management, Wi Fi connection and other details, as well as sound, notification, interface design and other details.

Silent mode added after missing on Android 5.0

General improvements in system stability

Improved RAM management

Fixes for sudden app closures

Improved battery management

Excessive consumption of network devices when used Wi-Fi fixed

Issues with wireless connections fixed

Problems with Okay Google function solved

Notifications problems solved

Some sound problems experience by certain devices fixed

Other improvements and changes

Changes in the Material Design color palette (after users complaints, possibly for a higher version though)

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