haha, youtube is pretty easy. If you can teach yourself how to make an iphone app you can handle that. if using mac just use imovie or windows window movie maker. both pretty straight forward.
So in the app do you have the option to switch between any open source maps? (like the ones I like in Gaia are ESRI USGS TOPO, or the newer CalTopo maps… I really liked the mytopo.com maps but they closed off their iphone source because they made their own sh*tty app.) . And is there just one zoom layer for all?
What i think you should do is contact Gaia GPS and try to work with them to integrate your app into Gaia. That way you could have the different map and zoom level options (if you can't now). and have the full power of Gaia with all your great PCT data (trail line,pix, waypoints, resupplies, water cashes) as an overlay.
You could still keep your app in the store but make the overlay data in Gaia available as an "In App" purchase