Nanu is a new Android app that boasts the ability to make free calls even via a slow 2G network connection, and more impressively, to non-Nanu users including landlines and mobile phone numbers. The calls are free because the app employs an ad-supported model where a short ad will play over the waiting tone before the calls are picked up. In the emerging global markets where 2G mobile network is still the norm, Nanu’s unique capacity would give it a definitive edge over its more bandwidth-demanding competitors, such as Skype and Viber. If the quality of Nanu’s Internet-based calls holds up, its price advantage over regular phonecall charges might even help it break into developed markets.