This is the best app for hiking that I have yet to find and I have tried several. I have used James Associates desktop MacGPSPro for years and uploaded routes to and downloaded track logs from my Garmin GPS. Now I can do the same with this iPhone app. It downloads USGS Topo maps in seconds over WiFi or a cellular data connection. And it can be used offline to follow a route and create a track log.
Waypoints may be created within the app or downloaded to it in .gpx format. What more could anyone want. I have used it for local hikes and for navigating National Wildlife Refuges during a recent trip to Florida. I have never had any problem with it. It has met my requirements and exceeded my expectations.
A terrific app at a very reasonable price.
Kingfisher500 about iHikeGPS : Classic Topo Maps, v5.0.3