Network Radio also known as push-to-talk over cellular (PToC), push-to-talk (PTT), LTE radio, is a method of one-to-one or one-to-many communication. It works just like conventional two-way radio (walkie-talkies) but uses the cellular data network rather than dedicated infrastructure.
The benefits to this are huge. The cellular data network is fast, cheap and ever expanding. Using this as a 'world-wide' repeater, allows virtually unlimited range communication that is fast to set up and cost effective to operate.