The Nexus 7 tablet jointly produced by Google and Asus has already begun shipping, according to sources in the component manufacturing arena.

It's expected to hit retail outlets sometime in July, with total shipments projected to top three million units before the end of 2012.

Google's I/O developer conference, taking place from 27 to 29 June in San Francisco, is where details about the tablet will be announced, as the rumours have suggested. It's expected that Jonney Shih, Asus' chairperson, will be in attendance to unveil the Nexus 7.

New reports suggest the tablet will be priced at $159 - $179 (£100 - £115), at the lower end of the $150 - $250 (£95 - £160) range originally expected. The device's attractive pricing will help it compete with Apple's iPad, which currently dominates the market in global tablet sales.

But the low cost of the Asus 7 also means it will ship with limited features; it will reportedly lack 3G or LTE capability, with Wi-Fi being the only means of connectivity. The tablet will also not feature a backside camera - just a front-facing webcam with likely a low resolution.

The device recently appeared in the metadata of two pictures apparently taken in a Google building, all but confirming its imminent launch.