The patient texts the code to a central database every day to earn cell - phone minutes. (www2.technologyreview.com)
Once you're subscribed to services like Cell Signs, House4Cell, or RI Tracker, just to name a few, you can post a special text code on your listings» For Sale signs. (realtormag.realtor.org)
Consumers simply scratch off the Sproxil security label affixed to an item at the factory to reveal a one - time - use numeric code, then text the code for free to a secure number to authenticate the product's origins. (entrepreneur.com)