It is a violation of U.S. copyright law to install Google Play on a device that does not come pre-loaded with the software. Google Play is closed source software that is subject to licensing agreements, and is not freely available for download as of 2015.
While the Android operating system is open source, Google's proprietary apps are not. These closed source apps include Google Play, YouTube, Google Maps and Gmail. Phone vendors must contact Google and arrange for a license to include these apps on their handsets.
Google does not offer Google Play as a download for consumers. Alternate app stores such as the Amazon Appstore are available to consumers whose devices do not support Google Play. Android applications offered as direct downloads by the manufacturers can also be installed on devices without Google Play.
Google maintains a list of devices compatible with Google Play. Certified devices include smartphones, tablets, game consoles and televisions. Cameras, portable media players and watches can also be Google Play certified. Major manufacturers whose devices appear on this list include Samsung, Sony, HTC and LG.
Google recommends that consumers with questions about a device's Google Play compatibility contact the device manufacturer. Google does not provide information or support regarding unsupported devices.