In countries where international long-distance rates are high, mobile services like mig33's mobile instant messenger and VoIP calls are starting to gain a sizable user base. The Burlingame, Calif. startup, which was an eTel/GigaOM Launch Pad startup, says it has signed up more than 7 million users to date and has added several new features, including Google Talk (GOOG).
The startup's 7 million members and growing user base actually surprised me a bit — the company said it had 6 million members in July — given that its main approach is to use downloadable mobile software. Mobile clients can often be a barrier to entry when attempting to build a sizable amount of users, particularly for services that are supposed to save users money. For those that don't want to download, the company also recently added a WAP site. Other mobile callback/calling type services that offer lower-cost minutes include Jajah and Cellity.