Samsung just keeps on releasing Android 6.0 Marshmallow updates for its devices. The latest one to be graced with this iteration of Android is the Galaxy On7, launched in 2015.
A 2016 version of the On7 has been outed by a benchmark result, and this will run Marshmallow from day one, so it's definitely good to see Samsung making the software available for the original On7 too, and not pushing people to buy the new model if they want an up-to-date Android experience.
So far the update is only available for On7 units bought from Turkey, but we assume it will make its way to more countries soon. The software in question is G600FXXU1APF8, and that will be your new build version once you apply the update. This should be rolling out over-the-air in Turkey within the next few days. An exact changelog isn't available yet, but expect to see all the new features that Google has baked into Marshmallow - Doze Mode and App Standby for improved battery life, a new granular permissions system, Now On Tap, and much more.