Google on Tuesday began selling a version of its Nexus One smartphone that works with AT&T's 3G wireless network, in a move that will allow it to compete with Apple’s iPhone.

Previously, the Nexus One smartphone had been running on the slower networks of AT&T, which is the primary network provider iPhone in the US.

Google has been trying hard to make its Nexus One surpass iPhone in popularity since it launched the phone in January, but the Android based Nexus One is selling at a much slower rate as compared with sales figures of the first iPhone.

Figures show that Google could manage to sell only 135,000 units of Nexus One in seventy-four days after its launch as compared with a total of one million sales of first iPhone device in the same time frame.

Commenting on the topic, mobile analyst firm Flurry said, "Despite the fact that the Google Nexus One is the most advanced Android handset to date, and enjoyed substantial buzz leading up to its release, the launch has been overshadowed by lower than expected sales.”

Flurry Inc added that the Nexus One could not take off because Google was selling the phone through its own website instead of teaming up with telecom service providers.