While there are offline navigation solutions out there that can do a great job in helping you reach your destination they are more or less paid applications. Google is rumored to introduce offline navigation in Maps as soon as this summer.
Google Maps already met data caching with the occasion of the version 5 release but a working data connection was still needed for changing a destination. According to Dutch sources, Google might introduce offline navigation in its Maps application as soon as this summer.
There’s neither official information nor confirmation of a specific release date or pricing but since the current mapping solution from Google is free we incline to believe the alleged offline variant will also cost zilch. Nokia is offering free offline turn-by-turn navigation via Ovi Maps but that bit is coming to Windows Phone 7 as effect of the Nokia-Microsoft partnership. It’s only logical that Google would be tempted for a counter-attack.