Exchange Services has been available in Android for a long time, but now it's also in the Play Store. As with other Google apps in the Play Store, that means it will be possible to improve the feature over time without waiting on OS updates. In fact, this version of Exchange Services will add some new capabilities.

Here's the changelog for Exchange Services v6.4.

This update, together with the latest Gmail app update, allows you to use the Gmail app with Microsoft Exchange ActiveSync. Some of the newest features you will get upon updating:
• Out of Office
• Rich Text Formatting
• Event Forwarding
• Support for EAS 16

With this Exchange Services update, you can use the Gmail app (latest update) with Exchange ActiveSync features. This is probably only a big deal for people who use Exchange for work, but it's still a common requirement in business. The app listing is still rolling out, so it might not show up for everyone yet. Give it some time, or grab the update from APK Mirror.