rebtelSwedish based internet calling service Rebtel has announced today that it has acquired Free World Dialing, a mobile calling application, from Talkster for an undisclosed amount. The company notes that under the agreement, Rebtel will now carry all of Talkster’s international calls and Free World Dialing customers will now have access to unlimited free international mobile calls between 52 countries.

The joined services will now offer customers a quick and easy way to call internationally from your mobile phones. To use, customers sign up for a free account, enter an international number into the contact form and receive a unique local number to store to their phone. The principle is that Rebtel will connect the local number to the international number through the internet, costing the customer only pennies instead of traditional international rates.

While former Talkster customers mainly used the service for international mobile calls, they will now have access to several additional Rebtel services, including Rebtel Computer Calls as well as Rebtel SMS for international text messaging.

Rebtel claims to be growing rapidly with over 100,000 new users per month and a total of more than 4 million customers worldwide. Revenue seems to be growing as well with a 75% revenue grow close to $20 million in 2009 and similar projections for 2010. A relatively safe prediction as 2010 has started off with an influx of former Talkster customers using the Rebtel services. Not to mention a recent acquisition of U.S.-based VoIP service, Gorilla Mobile, allowing the company to target low cost calling in Asia.

The beginning of the new year has seen some suprising moves with in the VoIP industry, including that of internet calling company JaJah for $207 million in cash by Spanish phone giant Telefonica. It will be interesting to see Rebtel’s next move and whether these newly acquired services are meant to attract a buyer or make a play at global VoIP dominance.

How To Make a Direct Call from Rebtel on Vimeo.