If you can't follow good practice to navigate over featureless terrain in no vis, then a whizzy phone isn't going to change the price of fish.
As for your 'high iron content ground' – thats getting pretty specific and extreme and very localised. If you have ventured there, you either know about it and know how to cope, or you don't and you are beyond your own limits.
If you need your location on a map, with a compass, confirming from another source, you need to be going out with someone who can use them properly.