Mobile reception in the Conwy valley, and in Trefriw itself, is fairly good (and 4G can usually be obtained).

However, once you start walking into the hills behind Trefriw, the signal can deteriorate quickly – varying on location – to a point where a signal can often only be found in the highest spots.

In addition to carrying a paper map, we’re fans of using O.S. 1:25,000 mapping on mobile phones, which will pinpoint your exact location at any point.  The O.S. have their own O.S. Mapping app, but Memory Map app is also good.  These apps use GPS, not a mobile signal, so will work wherever you go (though you should download the basemap first).

We’re also very fond of walk-tracking apps like Strava and Map My Walk.  Again, these use GPS, so don’t rely on a mobile signal to work.