There are a couple of ways of doing it if you have a spare handset. Works for both iOS and Android.
Get either a PAYG monthly SIM from the UK with good roaming or get a local SIM when you are in region and fit it into the spare.
Keep your normal phone on your UK number and check the roaming options.
3 do some great bundles that would cover you. Go Roam is their name for EU roaming.https://www.three.co.uk/payg-data-packs
They are usually very good if you pop into a shop and ask for the specific use case.
I don't work for them but have generally found their EU stuff better priced and more flexible.
Then just use Waze/GoogleMaps/etc