I am going to Spain in the fall with my brothers. My Virgin Mobile android (gingerbread) phone will not have service. I will need to rely on some type of WiFi communication. We'll be arriving at the Barcelona airport separately and I would like the others to be able to contact me, assuming I can connect to the airport WiFi. I do have a Google voice number but after researching I am still unsure if they can call or text me. They have US phones and will be arranging some type of international plan for the trip. WiFi calling would be nice but not required. I would at least like some type of messaging. We could all download the same app to facilitate communication but it would also need to be available for a windows phone and an iPhone. Are there any recommendations for apps that will work overseas? Thank you.