Raketu on Tuesday introduced a new voice over IP application that allows BlackBerry users to make cheap international calls, as well as send text-message and e-mail from within the application.

Raketu provides a Skype-like service that enables VoIP calls from computers and mobile devices. The company has set up "free calling zones" in over 40 countries where users can make free international phone calls. Users can purchase a $9.95, $24.95, or $49.95 package to pre-pay for minutes not included in the free zones, said a Raketu spokesman. In locations not covered by the free zones, Raketu charges a cheap calling rate, which varies in different countries.

The BlackBerry application is Web-based, which means users don't need to download and install software on their smartphones to use Raketu's service. Instead users can sign up and access the service by pointing their BlackBerry Web browsers at BlackBerry.raketu.com.

The application also can be used to send text messages globally at low international rates and to send e-mail.

The BlackBerry smartphone needs to have built-in Wi-Fi, however, since Raketu uses the Internet Protocol to send calls through. Research In Motion sells several models with the capability, including the BlackBerry Curve, the BlackBerry Pearl, and the BlackBerry 8800 Series.

Users do have another option. In November, Raketu introduced a Short Message Service-based application that doesn't need a Wi-Fi connection. It requires a user to send a text message to a local SMS number with embedded call instructions. Raketu then calls the user's number and connects it directly with the destination number.

In addition to a BlackBerry-specific application, Raketu has one optimized specifically for Apple's iPhone and iPod touch, which the company rolled out last month. It's also Web-based and can be accessed through the devices' Safari browser. In general, the service can be used on any smartphone with a Web browser.