Built with Asus, the tablet can be ordered starting today on , and will ship in the U.S. and three other countries in mid-July, said.

Google described the as principally a conduit for Google Play, its -based repository for Google apps and movies, books and other content. Nexus 7 is "built for Google Play," said Hugo Barra, product management director for at Google.

At Google I/O, its annual developer conference, Google also introduced a spherical Android-based device called Nexus Q that will work in homes to distribute music and other content over stereos and displays with controls from Android and tablets.

Google Play will launch on the home screen of the new tablet and buyers will get a $25 credit toward Google Play content, such a music, e-books and movies. The Nexus 7 screen has a 1280 x 800 resolution, useful in watching movies, games and other content, Barra said.

Google also listed a series of improvements in Android 4.1, including paid app encryption to help developers protect their intellectual property and an on-device speech recognition engine that eliminates the need for speech input to work over a wireless connection.