Pokemon GO AR+ mode now available on Android, but requires ARCore
The new feature requires Android users to download ARCore from the Google Play Store, which means that if your phone isn't compatible with ARCore, you won't be able to take advantage of the new AR experience.
The most obvious change you'll notice when you enable Pokemon GO AR+ is that whenever you locate a Pokemon, it will scale in size and will notice your movement. With Pokemon GO AR+, you'll have to get much closer before you throw your Poke Ball to make the Pokemon easier to catch (or even earn an Expert Handles bonus).
When using AR+ mode, you'll notice that Pokemon are displayed fixed to a point in your real-world environment. Also, keep in mind that Pokemon now have awareness of how close you are and how fast you are moving to them.