I remember being in college where some people would call someone like their parents with a collect call. "will you accept a collect call from Dave Ohara. My parents respond no." and, know I want them to call me. No cost to me, and my parents foot the bill. I never did this, but it is the idea behind India's use of missed calls on cell networks as a messaging bus.
GigaOm's Katie Fehrenbacher discusses the idea.
India’s “missed call” mobile ecosystem
How big is this? In India missed calls could be used as a messaging bus from half the users.
While the missed call system is increasingly fodder for entrepreneurs, the phenomenon has been a slight problem for the cell phones companies in India, as the free service seems to make up a significant portion of cellular traffic. According to a study from the Learning Initiatives on Reforms for Network Economies (Lirne) a couple of years ago, over half of Indian cellular subscribers made missed calls to convey a message.
Katie follows up today with a post on the use of missed calls for controlling remote irrigation water pumps.