Bring Along a WiFi Router and Create a Hotspot for the Whole Family
Bring along an inexpensive WiFi router. With a WiFi router and a local SIM, you can share a data package among your family. Everyone will have the connectivity and convenience of the internet as you travel and tour around. Use it for directions, Whatsapp, Skype, Factetime, WiFi calling, etc. You will need a separate SIM with a data package for the router. Most likely you will still want a another local SIM with voice for making local calls but you will not need extra data this SIM.