The iPhone now has a decent free sat-nav app in the shape of Navmii's Navfree. There are lots of maps available, and the usual range of destination entry options. The Points of Interest system is somewhat dysfunctional for UK users, but Google Local Search is on hand to use instead. Navfree isn't going to give premium sat-nav software from TomTom, Navigon and ALK too many nightmares, but at least now you won't need to pay if you only make the occasional journey.
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