With a DigitalGlobe Satellite Imagery subscription you can download imagery for an area of interest over wifi. You will then have imagery for that area saved to your TRX or TR GPS for use on the trail.
DigitalGlobe limits our downloads to 2GB per day, but other than that your subscription allows you to download as much as you want or need to during the 1 year period. At the end of the year, your imagery is still yours and you have the option to renew your subscription.
Watch the example video below to see how to preview, select and download imagery for your area of interest.