melkathi: Contextxtual actions are under the "Tasks" tab.
The contextual option is not always there. There must be something to do. So if you are at the beach near fishes, you may get the contextual button to go fishing.
To get the contextual button for updating your map, you will have to have collected all cairns of a specific type. So if there are eight (not sure about the number) cairns for the mountains, after you have found all of them, next time you camp, the option should show up.