VoIP provider Truphone reported Friday that it is preparing its service for Google's Android Nexus One phone. This follows the voice company's announcement that it is spreading its Wi-Fi based platform gradually to Android phones.

The Truphone service, currently available for several Nokia, Apple and BlackBerry handsets, is already operating on Truphone Android HTC G1s, Magic, and Hero models. The Truphone app is available as a free download via Android Market.

Calls made over Truphone's Wi-Fi platform are free, while calls made beyond Wi-Fi are billed at a low rate. Calls made to Google Talk and Skype users are also free when both parties are in Wi-Fi.

A company spokesperson said current applications are available for GSM-based phones -- AT&T and T-Mobile in the U.S. -- although the company is working on developing service for CDMA phones (Verizon Wireless and Sprint in the U.S.) However, certain calls can still be made to CDMA phones for a small charge.

The spokesperson said Truphone is working with Motorola to move the service to Android phones including to the Droid.

Since launching its Truphone beta service in 2005, Truphone has gradually emerged as a significant competitor to Skype. The company targeted mobile phones from its early days and has waited as robust 3G and 4G wireless networks have come its way to make the service globally available across several different phone brands.

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