I need a way (possibly a third-party application) that allows me to use maps and GPS without an Internet connection.
I don't use it by car, just for walking in cities. It would be nice if I could just copy all data relative to a particular city before going there for tourism.
The Google Maps app does not store maps reliably, so it is risky to rely on it without an Internet connection.
For England and much of Europe, ViewRanger is great. Supports Ordnance Survey and other official-type maps; also some open street map projects. But it is absolutely what I would use -- and do -- if I am hiking with a phone. For Android - ViewRanger
Have you tried BackCountry Navigator?
It has topo maps, open street maps, and aerial photography.
It has a 16 day demo and a paid license.
I haven't had a chance to try it myself yet, but I've heard good things about Maverick:
Maverick for Google Android - Code Sector
There is both a limited free and pay version.
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