Smartphones Operate Off-Grid With Push/Talk Device
Beartooth is a handheld device that works with your smartphone to keep you connected when there is no cell service.
Using your mobile phone in areas with low signal or an overloaded network can reduce connectivity, making it hard to stay in contact. A new device called Beartooth is an off grid network for your smartphone. Once the app is downloaded and your phone is paired to Beartooth, you can reach other users within 10 miles. Beartooth works as a long range link between you and other users. Your phone connects to Beartooth via Bluetooth technology over the 900 MHz ISM band.
High resolution offline topographic maps pinpoint the exact location of everyone in your group and locations refresh automatically through messaging. By creating off-grid maps, Beartooth hopes to establish a community of adventurers who will discover new paths and share experiences with would be trekkers. There are about 20,000 Beartooth devices currently supporting users all over the nation.
Source | http://www.springwise.com/