Ethan Zuckerman of the WorldChanging blog writes eloquently about the importance of mobile phones in low-income communities. He identifies three factors critical to the spread of mobile telephony: new versus replacement infrastructure, pay-as-you-go pricing, and used phones.

Zuckerman is right on. By leapfrogging landline infrastructure, developing communities have been able to adopt modern technology faster and cheaper than we have in the U.S., for example. Pay-as-you-go pricing, meanwhile, lets low-income consumers afford to make a call when they need to, rather than sign up for lengthy guaranteed contracts – as documented in this case study of Smart Communications in the Philippines. Used phones, operating on analog networks, are often more affordable than new GSM handsets - and the shipping containers they arrive in can even be used as shared-access, entrepreneur-run phone shops.

However, it’s only towards the end of his post where Zuckerman hits the nail on the head: “More fundamental than these three factors is the fact that very poor people are willing to pay money to communicate.” He cites Grameen Phone as an example – read the case study here. (PDF)

Mobile telephony is already profitable for the telecoms. Now the question is: how do we incorporate this leapfrog innovation into a range of pro-poor business models? Stay tuned.

This morning I read an article in the New York Times about a company that is providing English tutoring services to teenagers in California. What's interesting is that the teachers all live in India, and communicate with their students using the Internet. Growing Stars pays its teachers a monthly salary of 10,000 rupees ($230), twice what they would earn in entry-level jobs at local schools.

The article reminded me of another one I had seen about Chida Soft - a village BPO doing coding on legal paper for an US client. It is one of India’s first BPOs in

The Nextbillion.net Team is pleased to announce the launch of our new BOP Activity Database. The Database tracks innovative enterprises that offer products and services to underserved communities in developing countries, and is searchable either by keyword or through a variety of pre-defined categories. It is meant to serve as a knowledgebase for those interested in researching and developing sustainable business models that address the needs of the world’s poorest citizens. You can access the Activity Database by clicking on the link above, or by clicking here.

The 200 activities currently in the database represent only a small fraction of the creative work being done today. Do you know of a relevant BOP enterprise that should be included? Please tell us about it online. Once you are logged in, click on 'Submit an Activity' and then enter in the pertinent information.