With the latest version of Vopium for Android, users can make free calls over Wi-Fi and mobile data networks. Vopium automatically finds the lowest call rate on your mobile phone. International calls are made using Vopium'slow-rate server, while calls to local mobile phones are cheapest using local mobile providers. Vopium also offers an instant messaging feature, allowing users to chat on Facebook and Windows Live Messenger. Vopium is currently offering 15 minutes of free calls worldwide.

Vopium has improved its Android application and is now offering free calls to other mobile phones with Vopium on either Wi-Fi or mobile data networks.

Vopium features an advanced built-in phone function, which always finds the lowest rate for calls and text messages on your Android mobile phone- either via regular calls on your mobile, 3G or Wi-Fi network. International calls, for example, are made over Vopium's servers to the overseas mobile phone.

Vopium is already very popular among Android users and is downloaded more than 1,000 times every day from Android Market. Vopium was even elected as the 'Essential Android App 2010' by the major tech site CNET.com.

International calls at the lowest rates

With Vopium, calls to landline and mobile phones are offered at a very low rate, even if they do not have Vopium installed. Rates include calls to any landline or mobile phone in Thailand for just under three cents plus the local mobile rate - working out at about the same cost as a local call.

15 minutes of free worldwide calls

Vopium is currently offering 15 minutes of free calls to all new users, which is a great opportunity to try out the application on an Android mobile phone or one of the more than 900 other supported mobile phones. To get started, log onto http://www.vopium.com and enter your mobile phone number.

Vopium has been tested on several of the most popular Android phones such as HTC Desire, HTC Legend and Motorola Milestone/Droid.