After much speculation, Google finally launched the Nexus One mobile phone this week.

Described by Google as a "Superphone", the handset runs version 2.1 of the company's own Android platform and can best be described as the "Droid-Plus."

The Nexus One smartphone, which was manufactured by HTC, is Google's first attempt at making its own device that runs on its open source Android operating system.

The Google Nexus One

The phone's official unveiling comes just a couple of months after the similarly hyped Motorola Milestone (known as the Droid in other countries) came to market.

Yet despite all the anticipation, Google isn't adding anything radical to the Nexus One that will change the smartphone industry.

Rather, it's using the Nexus One as a showcase for the Android platform's potential and it has made sure that the device has the most cutting-edge hardware and software available on the market.

The Motorola Milestone

As ABI Research analyst Kevin Burden notes, the Nexus One may be Google's way of pushing device manufacturers to up their games by ensuring that their devices conform to Google's standards.

"One of the things they talked about during their presentation today was that they expected that the next version of the Droid will look like more Nexus One," Burden says.

"You've got to assume that they are building some services for Android and that those services will need so-called superphones that have 1GHz Snapdragon processors."

In this article, we'll break down the key differences between the Droid and the Nexus One, from the strengths of their processors to the versions of the Android operating system they run on.

The processors

The Droid utilises Texas Instruments' TI OMAP 3430 processor, which runs at 600MHz and was previously the fastest processor used in an Android-based phone.

The Nexus One easily outdoes this, however, as its 1GHz Qualcomm Snapdragon processor will give it faster computing ability than any other smartphone on the market. Google wants to use this faster application processor to give users the ability to run multiple complex applications at the same time.

The keyboards and display screens

The Droid was notable because it offered users both a touchscreen keyboard and a physical slide-out keypad. However, the Droid's physical keypad was often criticised for being too shallow and more difficult to use than other smartphone keyboards.

The Nexus One eschews the slideout keyboard altogether and sticks with the standard touchscreen keypad.

In terms of the display screen, the Droid has a 3.7in screen that uses Wide Video Graphics Array (WVGA) to display video at 854x480 pixels.

This actually makes it slightly finer than the Nexus One's WVGA display screen, which operates at 800x480 pixels.

The operating systems

This may not seem like much of a difference at first, as the Droid runs on Android 2.0 and the Nexus One operates on Android 2.1.

But Google says that it has added several key features to the 2.1 version of the operating system, including a voice-enabled keyboard that will let you vocally update your social networking sites and to speak text into any field, as well as the ability to have a 3D photo gallery.

The carriers

This Milestone is currently only available in the UK as a sim-free handset through Expansys, although the retailer is offering the phone for £49.99 when purchased with a T-Mobile contract.

The Nexus One, however, is available through Google's own webstore as either a sim-free handset, or  on Vodafone (although this is currently not available).

Both these handset fit with Google's vision that mobile phones should not be tied down to any specific carrier and that users should be able to switch carriers without having to switch their favourite devices.