Last week I made the following point at the Bank of Tanzania's conference: Right now you can buy a 5,000 TZS (about $2) bag of mchele (rice) for 5,000 in cash.
If you buy that same bag of mchele via mobile money it can cost up to 5,950 TZS. Doesn't matter how much fancy tech you have there is no cash-lite economy coming out of the above equation.