Vonage has become a veritable player in the home phone industry in the US, thanks to ultra-cheap rates for its Voice Over Internet Protocol calling system. Now it's making that service mobile via Android, and making a real case for VOIP-based service, if not VOIP-only phones. Customers who subscribe to Vonage at home can make domestic calls to anyone else with the app for free, and even those without an existing account can use the app to make calls to regular cell and landlines on a per-minute basis, Skype-style. The best part? It works on WiFi or mobile broadband, making Vonage a true mobile VOIP provider with no restrictions.