Here's how you can download the Root Checker app free for Android devices.
1. Go to the Google Play page for the free app Root Checker.
2. Tap the Install button.
Here's a description of Root Checker:
"The goal of this application is to provide even the newest Android user with a simple method to check their device for root (administrator/superuser) access.
This is a very simple application to notify the user whether or not they have properly setup root access.
This application will test the device for root access using a very simple, quick and reliable method to check for root access. The su binary is the most common binary used on Android devices to grant root access. This application will check and verify the su binary is located in a standard location on the device. This application will also confirms the proper permissions and flags on the su binary in addition to testing the access granted by the su binary."