Android 6.0 Marshmallow could be released on October 5 (for Nexus 5 and Nexus 6)12
But will Android 6.0 Marshmallow for older handsets be launched on that day, too? Well, we can't know for sure, but, according to Bell - one of Canada's largest mobile carriers - the Nexus 5 and Nexus 6 could be updated to the new version of Android on October 5. However, this date is subject to change.
Needless to say, the Nexus 5 and Nexus 6 should be the world's first handsets to get the Marshmallow update (Nexus smartphones are always the first to be updated). Of course, the October 5 date might be valid just for Canada, and we may see the Nexus 5 and 6 getting Android 6.0 Marshmallow sooner in the US. In any case, we should definitely expect updates to be rolled out not long after September 29.
Currently available only as a Developer Preview, Android 6.0 Marshmallow comes with plenty of novelties and improvements over Android Lollipop, including Android Pay, enhanced Google Now, standardized fingerprint support, a new power saving mode dubbed "doze", and so on.
via: Mobile Syrup