Have said phone whats the best way to use it for importing gpx files of routes and then navigating around them with the phone ?

Cheers

I wouldnt, the screen is not that tough due to that fact its flipping huge. I broke mine in a 'door' and had to get it replaced. Unless there is an adjustable iPhone mount which has some screen protection built in and can resist a high speed crash with the whole force on the screen. 😀

Are you using as a cycle computer or keeping it in a pocket?

(I keep my mobile pocketed but it still tracks no problem)

No not looking to use as a cycle computer as such, just as a means of uploading a route/file into it. And then using it to navigate around a trail thats new to me. The less time having to pull a map out the better.

Someone on here has done RMaps (which caches the map for offline viewing), and there's an OSmaps application too. I think (but i'm not sure), both allow you to import GPX files.
Try http://www.mapmyride.com, as well – I think that can export GPX files and their website mentioned something about Android, so they may have something on offer themselves.