As far as looking up coordinates, iPhones will store that with almost every photo you take, worldwide. If you click on the photo you can see all sorts of data. As for cell-phone coverage, it’s surprisingly good in the parts of Africa I’ve been to - even in the Caprivi. It borders on unbelievable, and certainly better than the rural parts of the US West. Cameroon, Burkina Faso, Ethiopia….. I have no idea.
As has been said, new iPhones are starting to partner with Starlink to provide basic text and emergency coverage to the entire planet. If I understand correctly, this is only working with T-mobile at the moment.