Google Earth is great. However, if you go outside of data coverage (4G, etc.), the maps and images do not download. A couple paid services provide downloadable maps. They store in your phone, laptop, tablet, etc. and integrate with the GPS program and chip (make sure your device has GPS). Some map programs cost $30.00 per year for the upgraded maps but, they even show the names, addresses, and phone numbers of the owners of the land you happen to be trespassing on. Highly Recommended.
HUNT by onXmaps - Public/Private Land Ownership maps for your GPS, Mobile Device, and Computer