PathAway, a software that may be known to GPS users that use bitmap charts for biking, hiking etc. on their PDA in particular, will come to the iPhone some time next year (which is - awesome!)!
PathAway is a powerful chart plotter that is capable of handling everything you might ever want to use. This includes custom charts, tracks, waypoints, POIs, routes, proximity alarms and all that other fancy stuff you might get from a GPS device, ever.
There also is a "Professional Edition" that will add wireless services to the already comprehensive feature list of the "Standard Edition" like life tracking or downloading (Google) maps over the air.
The regular price is 59,95 US$ for the Standard Edition and 95 US$ for the Professional Edition.