Sofian Hadiwijaya is a Fintech expert from Indonesia who has 4 years of experience in global Fintech and 2 years experience organizing Fintech events. The document discusses how cash is still the dominant form of payment for many Indonesians, especially in smaller cities, but companies like Uber see potential in the Indonesian market as they have experimented with cash payments successfully in other markets. It provides contact information for Sofian Hadiwijaya.