How do you access Google play store app on your device?

You can download and install apps through google's Play Store, which offers the largest collection of Android apps available. The Play Store comes pre-installed on all licensed Android devices and can be accessed via the Play Store app on the device or through the website on any browser. You can remotely purchase and install apps to any device you're signed into through any web browser in which you've signed into your google account.

There are third-party app distribution platforms as well. The most prominent of which is Amazon's Appstore for Android, which can be downloaded and installed through a relatively simple process of visiting their website and authorizing your device with your Amazon account.

Lastly, you can sideload apps onto your device by storing the APK locally on an SD card or a device's internal memory, then using Android's built-in package installer utility to install the app. You need to use a file browser (Astro File Manager, OI File Browser, etc) to select the APK. (There are other ways of installing an APK directly, but for the sake of simplicity I've only included instructions for the easiest method.)

Note that you must tick the box that says "Allow installation from unknown sources" in the system settings before you can install any app foreign to the Play Store. This option is located in Settings > Applications on Android 2.x and Settings > Security on Android 3.x and 4.x.