Originally Posted by
johnny99
Google Maps just started offering turn-by-turn real-time navigation for bicycle routes. Google Maps also allows you to cache maps so you don't need a data connection.
Google Maps allow you to cache the
pictures of the maps, but it does not allow you to cache the connectivity information. In other words, it can only cache the pretty pictures you can look at, but no more.
This means that Google Maps cannot be used for turn-by-turn navigation without a data connection. All turn turn-by-turn navigation routes are always calculated by Google servers. In order to generate a tun-by-turn route the data connection is absolutely always required.