Changelog from v4.0.4801.8882 to v4.1.5014.8880:

Enabled call-via-work - allowing Enterprise Voice enabled users to make and receive calls using your Enterprise Voice (Lync ID) number only. Connect with others using a single identity.

Added user controls for adjusting the sound/vibration for incoming notifications.

Improved the Lync status icon - know if you can receive IM messages.

Enabled copy of IM text to the clipboard.

Multiple bug fixes.

You can download the updated Android client using this link.