MotionX GPS is a very good GPS app, with open maps, and you can download a map radius rather than use data.
I also use roadtrip for fuel consumption, although going to try our Fuely soon as that seems popular, and on roadtrip, If I forget to add a fill-up it tends to up my MPG.
itorch4, for when I don't have my torch to hand
BBR best biking roads
Kindle app- books on the go
Tripadvisor- check out reviews of hotels, hostels, resturants
Tunein radio- world radio
'Life begins at the end of your comfort zone'-
UK to Asia on a DRZ400 2012-2013