Unfortunately, Android devices will likely never see significant support past 2 years because of the Linux kernel. The maintainers of the Linux kernel are open

Unfortunately, Android devices will likely never see significant support past 2 years because of the Linux kernel. The maintainers of the Linux kernel are openly hostile to maintaining ABI and API compatibility with drivers which is necessary to allow binary blob vendor drivers to work with newer kernels. Ideally this should encourage vendors to simply open source their drivers and integrate them upstream into the kernel. However, in practice it means that most phones are stuck with whatever kernel they shipped with pretty much forever. Personally, I'd like to see Google switch to a BSD-based kernel, at least as an alternative option. Most of the interesting parts of Android live far above kernel space anyway.