Even though major manufacturers like Samsung and LG are trying hard to get all their devices on Android Marshmallow, the adoption seems to have slowed down.
If we look at the current stats, only 13.3 percent of all Android smartphones are on Marshmallow while 30.1 percent are still on KitKat and around 35.1 percent on Lollipop. The KitKat figure is more alarming given it was launched in October 2013 and since then many devices haven't even transitioned to the next version of Android in almost 3 years.
With Android Nougat on its way, Android OEM's will have one more excuse to not update Android Lollipop devices to Marshmallow citing they would rather build on Nougat to save development costs. Samsung has been bashed for long, in delaying updates to its budget and Mid-range smartphones, but this year the company changed all that. Most of its last-gen 2015 and new 2016 line-up is now running on Android Marshmallow. LG and Motorola too have been relatively quick in rolling out Marshmallow updates for their smartphones.
But the likes of Chinese smartphone vendors, local Indian smartphone brands like Micromax, Intex, Lava are still launching devices with Lollipop on-board let alone update their previous-gen line-up. Google now needs to take stern action against these manufacturers, shaming them in public may not be the only answer.
Source: Android Developers