I can google pictues of interesting graffiti any time I like. Taking a picture devalues the moment.

I'm not sure where you are that you can't read the signs (but have cell service), but you would be really out on a limb if that's the case and you don't have anyone to help you out. I'd honestly find it kind of pathetic to watch.

If it's so important to message your wife, then it's a better idea not do it while also trying to walk around in public.