Before you can download a paid app, you must set up a billing arrangement.
Price/Install button
Indicates the cost or install for free apps.
From the Home screen, tap Play Store .
Tap a category from the homepage or tap the Search icon (in
the top right corner of the screen) to search for an app.
Tap INSTALL or the Price button to download the selected app.
If you agree with the app's access requirements, tap ACCEPT.
The app will be downloaded and installed.