The Best VoIP App for Android

Truphone is a free application available for download from the Android marketplace in the United States and United Kingdom. European language versions are in the process of being released, as of 2011. Designed for international use, it allows calls to other users anywhere in the world for the cost of a local call, plus a low-cost international fee. It also offers integration with instant messaging and social networking platforms such as MSN Messenger, Yahoo!, GoogleTalk and Twitter.

Vopium is an independent VoIP client that won the "Best VoIP app for Android" award from CNET U.K. Vopium, like Truphone, is also geared toward making international calls, with a focus on adaptive routing to keep calls as cheap as possible. You call a local number, and the software then forwards your call via the cheapest possible route. Vopium is also available for non-smartphones, which provides a greater chance of compatibility for the users you plan to call.

ISkoot produced the software for the first commercially-available Skype handsets produced by Mobile Network 3. As Skype now produces its own software, iSkoot now produces an independent application, available in specially tailored versions for different mobile networks, including AT&T;, Verizon and T-Mobile. Each of these apps also provides integration with your email and social networking accounts.

Skype is a major VoIP provider, and its mobile application is one of the most fully-featured. It provides full integration with the Android address book, combining mobile numbers and VoIP accounts into single entries, displaying a prompt asking whether you would like to use cellular or VoIP when you try to call or text them. Verizon 4G users can also make and receive video calls using the Skype application.