Nexus 9 is manufactured by HTC. It features an 8.9″ IPS LCD display with 1536 x 2048 resolution. It’s powered by an Nvidia Tegra K1 dual-core 2.3GHz processor and 2GB of RAM. Internal storage is available in either 16GB or 32GB. The Nexus 9 features a large 6700mAh battery, and 8MP camera, with 1080p video recording, along with a 2.1MP secondary front facing camera.
Google has released the Android 6.0 Marshmallow factory image for all versions of Nexus 9. Even if you have not received the OTA, you can manually update Nexus 9 to Android Marshmallow using this factory image. Detailed guide is given below.