Galaxy S7 & Galaxy S7 Edge
The Samsung Galaxy S7 and Galaxy S7 Edge were the devices that replaced the Galaxy S6, Galaxy S6 Edge, and Galaxy S6 Edge+. And despite the fact that they're one year older they, like the Galaxy S6 models, should be avoided in 2019. Here's why.
At this point, it looks like the Galaxy S7 and Galaxy S7 Edge will get left behind on Android Oreo. Samsung hasn't confirmed Android Pie upgrades and we aren't expecting a surprise release.
So if you want to get Samsung's latest features on a Galaxy S7 or Galaxy S7 Edge, you'll need to do it manually. You might not have the time, or patience, to do that.
Unlike the Galaxy S6 and Galaxy S6 Edge, software support for the Galaxy S7 and Galaxy S7 Edge hasn't ended.
That said, maintenance updates (bug fixes, security patches) have become infrequent and Samsung will likely pull the plug in the near future. And once that happens, you'll be on your own.
These devices have more dependable hardware and they'll receive software updates from Samsung and its partners for the foreseeable future.