Firm amassed over a million users in six months on iOS.
Hong Kong based Maaii claims two main differentiators from the many other VoIP apps out there. The first is that it integrates social network friends with those in a user's phone book. This means that, providing the other user is registered to Maaii, it's possible to call a Facebook friend, for example, directly from the app.
The second is free credit of $1.90 – 100 minutes – to all users on a daily basis.
Other features include predictive dialling, push notifications and international voice roaming, which allows users to make calls to landline and mobile numbers of friends who don’t yet have Maaii in more than 200 destinations.
Chris Lewis, VP of Maaii, said: "Our inclusion in Google Play demonstrates Maaii’s commitment to delivering extraordinary value to our growing user base. The successful launch of our iOS app resulted in a cascade of requests for access to our Android app and we’ve responded by opening up our beta testing to the public.
"The results thus far have been staggering, with tens of thousands of testers already participating."
Maaii has also launched an SDK to support HD voice in its app. It says this is the precursor to a range of SDK services that will form a suite of enriched platform services.