One of the things that make Android a great mobile operating system is variety. Because it is a free and open source OS, manufacturers are free to customize Android to incorporate their own unique features into each device. This results in a great number of choices among smartphones, with varying feature sets. The downside to this, of course, is fragmentation; because the operating system must be individually tailored to each hardware configuration and user interface, updates can often be delayed and inconsistent from one device to the next. And older devices that are outside of their upgrade period, which is typically two years from launch, won't get operating system upgrades at all. Thankfully, those who know how to perform advanced modifications on their devices can often install Android versions that have been custom made by developers and hobbyists to bring older devices into the present.
This happens to be the case with the Galaxy Nexus, which was made by Samsung and released about five years ago. Thanks to developers over at XDA, there is now an Android 7.1 Nougat-based ROM available for the Galaxy Nexus. To install the ROM on your device, you will, of course, need some knowledge of performing advanced functions on Android devices, as well as a rooted Galaxy Nexus with an unlocked bootloader and a custom recovery. Given the specifications of the hardware in the Galaxy Nexus in comparison to modern smartphones, it is likely that Nougat may not perform particularly well in terms of speed on the Galaxy Nexus, but for those itching to try out some new features, that may be a worthwhile trade-off.
As with any unofficial ROM, it should be noted that these builds may not be perfect, and users may experience some bugs and glitches from time to time. With that said, it is quite impressive that developers could release a Nougat-based ROM so quickly; as of the time of this writing, only two devices are currently running official builds of Android 7.1, Google's newly released Pixel and Pixel XL. Although many devices may not officially get updates after two years of life, it's nice to see the developer community showing some love for older devices by bringing them the latest version of Android.