I'm looking for a free GPS app (or apps) for both iPhone and Android that will supply an 8 figure UK grid reference. I don't need it to do anything else. I think I've found one for Android here: https://play.google.com/store/apps/details?id=net.blerg&hl=en_GB but I'm struggling to find one for iPhones. It needs to be free and simple as it is for 11/12 year olds in school.
In reply to DaveHK: Modern GPS modules can produce 3 meters accuracy. If it's double GPS/GLONASS module it can be even better because it uses both American and Russian independent positioning systems. Doing so increases accuracy by 0.4 coefficient.
Double modules are installed in all iPhones starting from 4S.