Get the navionics boat app, it's free, then get the us maps, it's 9.99. It will show the reefs, firing range with cans. also shows your tracks. Not sure about entering gps no's but it shows gps numbers as you move the pointer to a specific location, pretty good in my opinion. I have it on my zte android. Mike
I wish to die peacefully in my sleep like my grandfather, not screaming like his passengers.