DeLorme's inReach Explorer (3) rounded out the group with its feature-rich display and Iridium satellite connectivity. The inReach offers two-way texting to phone numbers entered on a computer before your trip. This provides welcome assurance to loved ones back home, and could prove incredibly useful during a rescue situation. With the inReach's built-in compass and downloadable topo maps, it also serves as a fully functional GPS. It will even connect to your Twitter and Facebook accounts. Update if you must, but don't cry to us if you get caught in an emergency only to find your last backcountry tweet killed your batteries (inreachdelorme.com, $370 plus service plan starting at $15/month, no annual contract required).