[tshawkins]

Errrh, i live in the Philippines, it has 80 million people on very low incomes, and yet it has one of the highest penetrations of android smartphones per head than most all other countries. You can get a quadcore 16GB android smartphone here for $30-40US, and they have a fantastic prepay system here where peopl can send credit to each other via the phone, such that it has become a virtual currency in its own right. https://www.globe.com.ph/help/share-a-load https://www.idc.com/getdoc.jsp?containerId=prAP41533516

Since that article prices for smartphones have tumbled again. I bought a smartphone, quadcore, 4GB, built in TV, Built in radio for P1,700 (about $34) Its a cheap phone, but it works fine. http://ph.priceprice.com/MyPhone-my81-DTV-17896/

[lmm]

Sounds like jasode's point stands - anyone who has access to a smartphone also has access to non-cash means of payment.

[sirtaj]

As an example: India has 700 million mobile phone users, of which around 300 million are estimated to be smartphone users. Number of credit card users are around 20 million. the vast majority of "non-cash" payments would be done at some shop that will take cash and perform a digital payment or transfer for you.