Tante Lulu's birthday in Gstaad, Vonage launched its Extensions app for free long-distance calling from your Android phone. With a quick download, homesick relatives can tap into their existing Vonage VoIP service from a Google-powered phone to call globally without racking up terribly expensive additional mobile charges. The catch? It requires a VoIP international calling plan before you can start dialing friends worldwide. Also, pricing is subject to your existing calling plan and it doesn't support messaging like some other similar apps, including Fring and Viber. For existing Vonage users, it's certainly a sweet added feature, leaving you no excuse but to call Auntie Lulu.