I talked to many farmers, as part of the interviews I did on the way they adapted to changes in the climate. Curiously enough, mobile phones played a significant role in that.To really understand it, one has to comprehend the difference between living in a remote village in Africa, and living in Europe or North America. Up to recently, even the simplest of tasks was complex, because people could not get in touch with each other.In Africa, if my neighbour Charles left for the market, 10 km further, there was no way to get in touch with him. I could not ask to buy a bag of fertilizer, or to check on the prices of maize, or to see if a supplier had sorghum seeds in stock. Short of actually going there, I would not know. I would never know, as Charles might not have looked for the information or goods while he as at the market.Information did not flow. And information is power, certainly in rural Africa.Helene, in Burkina explained how she called around to colleague farmers in different areas to check on the market prices for vegetables. Andrew in Ghana uses his mobile phone to get in regular contact with his extension worker. During the planting season, Petri uses his GSM to trace the contractor who has a tractor. And during a visit to a studio from a farmer's radio in North Burkina, I saw how different farmers from all over the region called into a live programme, with advise on a particular problem a farmer had with pests in his tomatoes. Using their mobile phones.Naapi, in Lawra, on the border of Ghana and Burkina, explained how matters as simple as "talking to the guy next door", were complex. "In the past, it often happened I saw a colleague, on his field further down the hill, but I could not contact him. Unless if I walked to his field, I could not even ask him if he had a axe I could lend. So in the past, I would walked to him, often in vain, as what I needed, he did not have. Hours and efforts wasted. Now, I just pick up the phone and call him."Wherever I stopped on the 2,000 miles we drove in West Africa, there were scratch cards available, and different networks covering the areas, no matter how remote they were. People used mobile phones, even if it meant they had to go to the next village to charge the phone, as many had no electricity in their house.True, in West Africa, the use of mobile phones for farmer support "call centres", was not as developed as in Kenya. And the system to pay, or transfer funds, through mobile phones (like the M-Pesa system from Kenya's Safaricom), was just starting up, there is no doubt that mobile phone connectivity is key to rural development.And it has just started.