The good news is that the Android upgrade to version 6.0 (otherwise known as Android M or Marshmallow) is starting to roll out on a lot of Android flagship phones, including those from Samsung, HTC, and Motorola. LG was one of the first to make the promise that their devices would be one of the first to receive Marshmallow, and they have done well to keep that promise. This is the latest news on Android M Version 6.0 Marshmallow Release Date for LG G5, G4, G3, G2, G Stylo, and V10 on Sprint, Verizon, US Cellular, T-Mobile, and AT&T.
At this point in time, there is no point in talking about the new LG G5 flagship phone, as it comes with Android M straight out of the packaging. In fact, I can almost say the same thing about the LG G4, last year's flagship phone, as it is pretty much taken care of as far as U.S. carriers are concerned. Android Authority reports that Sprint was the first to get Marshmallow as of last December, and then US Cellular followed one month later. February was the month that the last three carriers of T-Mobile, AT&T, and Verizon all got it.
As far as the flagship from two years ago is concerned with the LG G3, it will be rolling out there too. Neurogadget reveals that T-Mobile is still in their testing stage, but only Verizon seems to have it out for the LG G3, at least so far.
Then there is the V10. There are reports that the International version has been unlocked, and, like the LG G3, the update has rolled out for the V10 on Verizon.
So it looks like Verizon has been getting all the updates for LG devices, but not quite. The LG G Stylo has received its Android upgrade, provided you are with T-Mobile.
The big question mark remains with the LG G2, and there is a chance that this particular flagship from three years ago could be receiving the Android upgrade. Apparently, a report reveals that the Verizon LG G2 that was running on Android Marshmallow was spotted being benchmarked. There is a report saying that a custom ROM has been made for the G2, so users that want Android M on their G2 could get it, assuming that you know what you are doing with the custom ROM installation.
It is quite possible that your LG device already has Android 6.0 ready to download for an Over The Air (OTA) update. Users are encouraged to check your "Settings" and "System Updates" to see if Marshmallow is ready to download. The upgrade might not be ready depending on your U.S. carrier, as it has been shown that Verizon and T-Mobile have Marshmallow available, but some of the other carriers like US Cellular, Sprint, and AT&T do not.