The map screen on the Edge 840 is terrible, and one of the biggest factors is the stupid positioning of the hand icon directly in front of your pointer when the map is orientated in the direction of travel. Here is a picture I borrowed from the last complaint about the topic, but that complaint is locked and the problem is still there, so I'm adding a new complaint.

On the 830 that icon, and the zoom icons to either side, only appeared for a short time after you tapped the map. That would be the best arrangement. The second best would be to have that icon somewhere else. The situation as it is is plainly stupid because it literally means you can't see the route. It needs to be fixed, and I am stunned that there are complaints here dating back over a year and it still hasn't been fixed. The people at Garmin should be embarrassed.