Google Maps is pre-installed on almost every Android device and can be installed on iOS ones. It offers the option of storing maps and information for offline use on your phone – to do so, select “Offline Maps” in the menu.
It's even possible to navigate within this selected area without mobile reception. However, the offline map does not contain as much information as its online counterpart.
Google also offers the Trips app, which picks out information and tips for them.
Of course there are alternatives to Google Maps. Alexander Spier from c't magazine recommends the free, open-source OsmAnd Maps, which uses OpenStreetMap (OSM) data. It has a wide range of maps for pedestrians, motorists, skiers or sailors, the information it shows can be customized, and it can be used online or offline.
Other free options include Here WeGo or MapFactor GPS Navigation Maps. Sometimes a specific destination also offers its own map app.
A prerequisite for all of these apps is an up-to-date smartphone with GPS reception and sufficient memory. Maps downloaded for offline use can be several hundred megabytes in size; (19659001) For the apps to work, they have got permission to access the smartphone's location and GPS has to be enabled. GPS does not need an Internet connection or even a phone call, but it does consume a lot of energy. – dpa