After a seemingly endless wait, Android 5.1.1 is finally available on the Nexus 9.
Google had announced that 5.1.1 was set to roll out on May 7, but it has taken several days for the update to start to filter out. The majority of Nexus 9s should now be receiving the update. Once it’s installed, the build number should change to LMY47X.
At around 400MB, the 5.1.1 update is significantly larger on the Nexus 9 than on other Nexus devices.
However, if the OTA update still isn’t showing up for you, Google has also posted the Nexus 9 WiFi 5.1.1 factory image to its website. The LTE version still hasn’t been updated just yet.
As Daniel notes in his post, it’s been speculated that the Nexus 9’s Tegra K1 system-on-chip, which is not present in any other Nexus device, caused the delay in getting the device updated to 5.1.1.
Via: Android Police