1. http://www.pewglobal.org/2016/02/22/smartphone-ownership-and-internet-usage-continues-to-climb-in-emerging-economies/
2. http://www.pewinternet.org/2015/04/01/us-smartphone-use-in-2015/
3. http://www.ericsson.com/mobility-report
4. https://populationpyramid.net
5. http://www.imshealth.com/en/thought-leadership/ims-institute/reports/patient-adoption-of-mhealth