Senior analyst James Wang of Digitimes Research believes that Google's recently announced Nexus 10, developed in cooperation from Samsung Electronics, and upgraded storage for the Nexus 7, are aimed at starting competition with players such as Apple, Amazon, Barnes & Noble and China-based white-box tablet vendors.

Since Google has prepared a full-range of tablet products, Wang believes the company's entry-level Nexus tablet, that has not yet been announced, will have the strongest influence on its competitors.

Google's Nexus 7 shipments performed better than expected, and are forecast to reach 4.3 million units in 2012, accounting for about 20% of non-Apple tablet shipments (excluding white-box models), while the volume in the fourth quarter is also expected to enjoy sequential growth despite the weak global economy, Wang pointed out.

Digitimes Research estimates that Google's Nexus series tablets will see total shipments of 19 million units in 2013 accounting for 50% of non-Apple tablet shipments.