Firstly, your family don’t need to check the accuracy. It’s very impressive. Do they need to check the accuracy of this 3 word thing?
Yet you say that you do check the accuracy? How do people unfamiliar with the app know that it's accurate? Remember the Apple Maps fiasco in 2012? Pontypridd was shown 6 miles (10 kilometres) northeast of its actual location, Stratford-upon-Avon, was missing altogether and if you looked up "London" you were directed to the Canadian city London instead of its namesake!
As for W3W, it's the same database, so what it says is the location address on my copy of the app would also be what it says on yours.
Secondly, if I knew how to post pictures, I’d post the screenshot showing how simple the app is. It couldn’t be easier.
And this is pretty much my point. I know how to post pictures. I could just say 'Oh, it's easy. I don't see why anyone else can't' but I realise that not everyone can.
And I realise that not everyone can read maps, or interpret co-ordinates, or even describe where they are.
If W3W doesn't suit you, fine, don't use it. I really only started the thread to see what experience others have had with it, but seem to have ended up defending it to all and sundry, as if I was the I one that invented it!
Thirdly, it is possible to select (from a simple menu) latitude and longitude values which are universally applicable the world over.
In fact anywhere outside OS areas return lat and long by default
So now it's not a simple button press? Your simple app has now got more complicated.
If you understand lat. and long., and how to use them, great. If you don't, they are completely useless to you.