Our design team at Dalberg recently interviewed potential customers for a mobile savings service in Indonesia, and found that they understood and appreciated the value of their savings if it were converted into more familiar units, such as kilograms of rice or liters of cooking oil. This is particularly true for the digital savings accounts that our client, a mobile operator, was bringing to market. Digital money is much less tangible than physical currency, so the metaphor of oil or rice increased confidence for new users of the service.