Just as a FYI for all US located folks with smart phones, I use t-Mobile as my service provider. They allow you to use your full US data plan in 140 foreign countries including France, Portugal and Spain for FREE. Voice calls anywhere are 20 Euro cents per minute.
So, I was able to use my 5 Gb monthly data for free messaging / texting and data all over Spain. Their Spanish roaming partner is Movistar. I had excellent signal strength from Madrid to Santiago this past April. In fact, I get stronger cellular and data signals anywhere in Europe than I d o here in the US. It is embarrassing actually. As soon as I powered up on landing at Madrid, I had five dots of signal.
I earlier traveled to Belgium, during March, to visit friends there. It worked great in Belgium as well.
I used my iPhone for GPS navigation and Google Maps in town, as well as frequent internet searches. I used texting easily throughout my travels. When placing overseas voice calls, I used the available, free, Wi-Fi in cafes or hotels, hostals or wherever I was to place "voice only" calls over Face Time.
I imagine the same protocols would work using Skype or whatever app the Android folks use...
My most used apps on this last Camino were:
- Maps.me - Worked better than the Wikiloc app, IMHO. It is a free download for Android or iPhone.
- Google Maps - Maps.me easily gets you to the edge of town, but Google Maps literally tells you, in English, how to arrive at an urban address, like a hotel, bus station, or shop. This is key if you have never been to a place before. When you are cold, wet, tired and in pain, it is a lifesaver!
- Eltiempo.es - The most comprehensive weather source I found for small Spanish villages and hamlets, along the Camino Madrid and Frances.
- Misas.org - Locates Catholic Masses anywhere in Spain, using the province and town. It links to the maps apps on your phone as well.
- ALSA - the national bus carrier who provides most inter-city bus support
- Rome2Rio - a hugely powerful app. Tell it any places on earth you want to travel from and to, and it will come back with car, bus, taxi, train, and plane solutions, including hybrid solutions involving multiple types of travel. I was amazed, it worked even along the Camino in Spain.
- Messages - the native Apple iOS text application
I hope this all helps someone...