Most Chinese phones might still be shipping with Android KitKat, but the grass certainly looks greener on the Western side of the hemisphere.
Google today officially announced Android v5.1 Lollipop, with incremental changes over the existing v5.0 iteration. Other than the typical ‘stability and performance’ improvements, Android v5.1 Lollipop brings the much needed support for dual SIM card phones. Android phones have been running dual SIMs since forever, but this is the first time that Android will support the feature natively, i.e., without requiring additional modifications from OEMs.
The other couple of things that v5.1 Lollipop brings is support for what Google calls ‘HD voice’, which, however, works only between phones that both run v5.1 Lollipop. Since security and privacy are among the fastest growing concerns, Google also brings in Device Protection, wherein if your device gets stolen/misplaced, it requires your Google credentials to be inputted to unlock. This works even if the device is factory resetted, which is what brings the most value as far as I’m concerned.
As always, Nexus devices — namely the Nexus 4, 5 and 7 — are the first ones to get this update. Chinese phones might, however, take a while before getting the v5.1 Lollipop update.[Source]