Best way for members of four families to communicate while on the same tour

If your phones are unlocked, you can always buy a local SIM card for your phone. Otherwise, you may have to look at other options. Who is your carrier? And is everyone on the same carrier?

Check to see what International Plans your carriers offer.

Use WhatsApp

Unless your cell provider has a good international plan (I.e. T-Mobil) you would probably be better of if everyone purchased a local SIM card. One exception would be if you were on the same family contract (which is not likely from your title).

if we have free wifi, we use whatsap, works great. otherwise we use travelsim cards in our unlocked phones that have free unlimited texts between them. just great for simple messages and no cost. we bought some more for our next trip in a few weeks. we set them up at home before we go, so we don't waste time on holidays and we know they all work. and we can give everyone at home etc our phone number before we get there.
hope this helps

swoboda,

I assume at least one person from each family will be taking a cellphone on the trip? Be sure to check that the phones will in fact work on European networks, as some networks may not work. Also check with your home cell networks to determine international roaming costs. The easiest solution will be to have international roaming with data capability, as that way you'll be able to text back-and-forth regardless of whether there's a WiFi point available.

What is the primary reason you need to communicate? Just in case someone gets lost/separated from the group? To coordinate meal times? Snapchatting? Your answers will determine whether you need a phone that is on all the time and what options would work better for that purpose. The options have been discussed already - a local SIM, purchase an overseas plan from your US cellular carrier(s), or relying exclusive on wifi (not a good option). One idea might be to designate one person from each of the four families to be the phone contact, so you don't have to buy international plan for everyone's phone.

I suspect that someone in each family has an older cellphone. Purchase the appropriate local sim for that phone (make sure it is unlocked prior to leaving the US). This process will give a phone to communicate between groups while leaving your usual phones untouched and available for communicating as needed with the US or other emergencies.

We used this approach for communicating between our narrowboats last summer.

On all the tours my family and I have been on together, we just used the iMessage/texting on our iPhones to stay in touch with each other. Don't know how useful this information would be if you didn't have iPhones, though! My friend stayed in touch with me while on her round the world cruise last year via WhatsApp. Worked very well at no cost to either of us.

If these people are on the same tour at the same time, might they already be together so they can communicate in person? :-)

If they are on their own, Whatsapp comes to mind. If everyone in these 4 families needs to be in constant contact and they are not in an area in which wifi is ubiquitous, think about how much each person truly needs to communicate on line as it can get expensive between data plans & SIM cards.

You could consider 2 way radios. Lots of families use them on vacation. Just be aware that North American FRS/GMRS frequencies are prohibited in Europe. You can buy the permitted PMR446 handsets for as little as $50 for a pair. They are good up to a couple of kilometres, but obstructions can interfere with reception.