app - interactive map / route planner ?

try www.scribblemaps.com

Above is not an app but exactly what you need - plan your trip at home on your PC or Laptop and then just access it via the internet on your smart phone.
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Sorry should have said a bit more on my post, but i've used scribblemaps the other day to add pins for cities i'm going to visit with notes like hotels etc and also a line from city to city.
You can then save it as a jpg which is good for websites and sending to friends and family, or use the map online and do all sorts of stuff.

I'm sure i tested it on my ipad and it worked also.

great, many thanks - that was very useful!

Brilliant!! I have been looking for something like that for ages!! Thanks...

An additional feature besides from saving your map as a jpeg-image is export a kml file which you can load into your Google Earth data base and view it in GE.
Among many other export options of course.

http://scribblemaps.com/
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