Again, thanks for a very prompt and useful reply! These guys have written quite a nice article on using smartphone navigation
where I think they pre-plan their route (without wifi) by just dropping pins at the intersections and then following the breadcrumb trail of pins.
Most of my route will be preplanned (I use gpsies.com) but it is nice to have the ability to go off-plan at times. Re the lack of digital road info in India, I’m sure it is no worse than the best paper maps : )
I´ll report back on on my PE experience with iPhone 5S when I get back..
Thanks again.