Excerpt from article on India:

Conducting a breakout session during World Water Week in Stockholm last year, Akvo’s Bjelkeman-Pettersson demonstrated the mobile-phone-enabled water-quality tests that their lab in Bengaluru uses. One kit contains a simple strip test, say for pH or phosphates. Another consists of a collection jar and a reactant chemical that can test for fluoride — a big problem in India and Bangladesh. There, too much fluoride in the drinking water has led to mass fluorosis, a condition that leads to calcification of ligaments.

“This [fluoride] test on a mobile phone is of equivalent quality as an ion selector device used in the lab; the difference is this cheaper and portable,” Bjelkeman-Pettersson says. The data is calibrated, interpreted and sent to the cloud with time stamps and GPS markers. The test can be extended to check chlorine, bacteria levels in the water, and, soon, arsenic — another big problem in the Indian subcontinent.

* Full article online at http://www.npr.org/sections/goatsandsoda/2017/06/07/527898124/if-you-see-dirty-water-dont-just-gripe-talk-to-the-cloud