City Maps 2go
City Maps 2go currently available for half price at $0.99 is a great offline solution. These maps are actual files on your iPhone, so you don't need to worry about losing coverage, being in another country unable to use your SIM or any other situation where you have no use of network or Wi-Fi. You have unlimited downloads and to give you an idea of how much is available to you, the current international area maps in addition to 400 US and 200 UK maps include; Paris, Berlin, Hong Kong, Bejing, Munich, Rome, Barcelona, Singapore, Cologne, Bangkok, Vienna, Hamburg, Amsterdam, Venice, Milan, Shanghai, Copenhagen, Zurich, Dusseldorf, Cairo, Toronto, Buenos Aires, Oslo, Frankfurt, Dubai, Istanbul, Florence, Lisbon, Prague, Tokyo, Brussels, Sydney, Manila, Seoul, Miami and Madrid, with the number growing almost daily.
To get the maps in the first instance you will need Wi-Fi to download them, but they are easy to read, ideal for offline use and well worth the mere cents they cost, and as the maps are on your iPhone already you can use the search facility offline.
A top maps app for those on the go where coverage may be an issue.