The research was done in Sri Lanka, but it was first reported on in India, then in Bangladesh and now the Sri Lankan English-language Sunday newspaper with the largest circulation has chosen to reprint what Nalaka Gunawardene wrote for SciDev. Now we need to work on Pakistan and Nepal. City planners need to know where people live and congregate, when and how they move, their economic conditions, where they spend their money, and about their social networks. Currently the best big data source for these variables involves mobile phones – ubiquitous device used by the rich and poor alike. Mobile network big data (MNBD) is produced by all phones, smart and otherwise, and include call detail records (CDRs) generated when calls and texts are sent or received, web is accessed, and prepaid values are loaded.