OnXMaps is awesome for scouting and knowing what land you're on if you're in an area that's a mix of public and private. It works great just running of the GPS of your phone.

For tracking my whitetail hunts, I use the Quiver Hunting App. It gives you all the hunting specific weather you need. You can also track individual hunts and log deer activity almost like a journal. It's free too! https://itunes.apple.com/app/id982722720