Google is trying to do Android owners a solid. The company has extracted its stock email app for Android and pushed it out to the Google Play Store. You're probably thinking, "Don't I already have an email app?" You do. What's different is that this email client isn't tied to the Android platform, and can operate on its own.
Unlike the standard Gmail app, this one takes an all-in-one inbox approach, letting you pull in messages from Yahoo, Outlook, and Hotmail. With support for IMAP, POP3 and Exchange accounts, the app also lets you decide which folders to sync.
One of the key benefits of separating the email app from the Android platform as a whole is that you won't have to wait for an update to all of Android just to update the mail app. Instead, this standalone app can be patched and tweaked immediately, without affecting the rest of the OS. Notable "updates" in this first version include increased Gmail security, easier account setup, and the ability to print.
It's worth pointing out that the Google email app isn't available to all Android users, only to recent Nexus devices and select Google Play Edition smartphones. I suspect that Google will cast a wider net later on and offer this email app to additional devices.