One of the things that Apple and iOS can hold over the Android ecosystem is how fast OS updates on iPhones and iPad are installed. However, compared to the abundance of potential hardware available in the Android ecosystem, Apple is restricted to a relatively smaller set. It has been a problem with Android from the start, and in 2017, Google took steps to make the update process smoother with Project Treble, which split the OS framework off from the low-level vendor implementation in each handset.
Link: Google and Qualcomm combine to make updating Android on Snapdragons easier
via http://www.zdnet.com