In light of the ‘Stagefright’ Exploit that is currently making a splash in the realm of mobile device news, Google has recently announced that it will be implementing monthly updates for certain generation Nexus devices.
More details about the regular monthly updates for Google Nexus devices can be found in the link below.
http://www.engadget.com/2015/08/05/google-nexus-monthly-security-updates/
https://support.google.com/nexus/answer/4457705?hl=en-CA&ref_topic=3415518