City Maps 2Go for iPhone.
You can't always rely on mobile internet when you're lost abroad, which is why it's handy to have offline maps stored on your phone.
Google Maps lets you save some maps offline, but it complains if you try to cover too much ground. Offline storage isn't available at all in some areas, so you might need a fallback.
Both City Maps 2Go and PocketEarth offer street-level maps for cities, regions and provinces, but only PocketEarth offers entire countries. Maps are free once but PocketEarth's files are much smaller – for example 11 megabytes (MB) for Tokyo compared to City Maps 2Go's 22MB. If you need maps on the run then PocketEarth might be more practical, but it's best to download them at home before you travel (all of Japan is a hefty 565MB).
PocketEarth for iPhone.
Both apps let you search for locations and points of interest by keyword, but PocketEarth also lets you specify a category to narrow down your search. By default, PocketEarth only searches in a 2-kilometre radius, which you'll want to push out to 64 kilometres if you're searching an entire city. Both apps also incorporate tourist information, but City Maps 2Go makes it easier to call up Wikipedia entries.
City Maps 2Go's maps look less cluttered until you zoom in. In Tokyo, much of the point of interest information is written in Japanese kanji, which not everyone will find helpful. PocketEarth only uses icons to mark points of interest, letting you tap for more information. You can also add and remove map layers to make the maps easier to read.
PocketEarth's standout feature is basic routing, offering a list of directions and a line on the map but not real-time turn-by-turn instructions. You need internet access to plan routes, but you can save them for offline use.
Even if you don't need the navigation features, PocketEarth's less cluttered street-level maps and ability to edit layers makes it easier to see where you're going.
City Maps 2Go