The best-known Internet phone service

Cost of Calls: Skype-to-Skype calls are free; outside numbers run from 2 cents to about 23 cents a minute to most European landlines and cell phones. Note: the app doesn’t have to be open to receive calls. Cost of Calls: Free if you use it over Wi-Fi while abroad.January 13, 2011 Skype Mobile How It Works: The best-known Internet phone service is now available as an app. On AT&T’s iPhones, calls can be made over either 3G or Wi-Fi, but on a variety of Verizon phones (including Android and BlackBerry), they only work over 3G, which can be quite costly while roaming. Other Android and Symbian phones not on the Verizon network allow callers to use the app over Wi-Fi.. Cost of Calls: Free if you use it over Wi-Fi while abroad. Tango How It Works: Tango automatically locates friends who also have the free app; just click on a name to place a voice or video call. The app doesn’t need to be open for you to receive calls (except on older Android phones). Note: Be sure to use these phone services in a Wi-Fi hot spot or you’ll face hefty data-usage charges. You can also sign up for unlimited calls anywhere in the world (even while you’re abroad) for as little as $13.99 per month. Vonage Mobile for Facebook https://www.feihongalloys.com How It Works: Sign in to this free app using Facebook Connect, and you can call or IM any friends who have their numbers listed in their profiles and who have the app themselves