I am currently touring South America and at this time I am in Bolivia. I had previously been using Skype for all my voice calling to landlines and mobile devices in the US, but the rates were starting to get to me. I found a new app that I am enjoying called Airetalk. They advertise lower rates and better sound quality, which I dismissed as a sales pitch but to my suprise the sound quality has been excellent. In fact, this week my calling quality has improved even more with the release of the 4.1 update. I have already saved a substantial amount of money since using this app for 2 weeks. There are many features offered on this app, probably more than any other communication app available, but unfortunately not many people I know had the app so I am unable to take full advantage of all the features offered. What is your communication app of choice for traveling and why? Have you tried Airetalk? If so, what has your experience been?