Ever hear of the Multipeer Connectivity framework? No reason you should, unless you are an iOS developer and keep up with the latest and greatest evolutions in networking. But this is a game changer.
Multipeer Connectivity means your messaging data can find its way to the internet and back by pinballing off other devices using WiFi and Bluetooth to move from device to device. As long as some part of the chain is connected to the net, your message will find its way. The requirement is that all the devices in the chain support Multipeer Connectivity.
Apple’s own AirDrop uses Multipeer, and there are other apps as well.
Here’s an example. There’s an ultramarathon that takes place in California each year on a trail called Skyline-to-the-Sea. It’s a roughly 30 mile trail through giant redwood forests where there is no cell connectivity. Using FireChat or some other app that uses iOS 7’s Multipeer Connectivity Framework, race volunteers, staff and participants could extend Internet connectivity and communication in an ad hoc mesh network that extends the length of the course.
The benefit of such an ad-hoc network is how trivially easy it is to set up. Everybody just use FireChat or AirDrop or any other similar app. Boom! Connectivity for everyone.
You can imagine the uses in a disaster area where cell towers have been knocked out, or other situations where people need to communicate but where no WiFi or mobile broadband is available.
In many poor countries and areas, people might be able to afford cheap or used phones, but not wireless service fees. Wireless mesh networks can provide free Internet connectivity to entire villages, slums or towns.
Nice job explaining all this by Mike Elgan.