Mobile-banking – making banking transactions through mobile devices like smart phones – might improve financial decision-making by customers. My study finds customers to retrieve information about their financial situation more often after adopting mobile-banking. In addition, I document that the higher transparency about the financial situation is associated with improved financial-decision-making of mobile-banking users. Concretely, I find mobile-banking adopters to suffer less from high-interest overdraft debt. Additionally, mobile-banking adopters reduce overdraft interest and fees by reducing consumption spending, increase credit card utilization and transfer liquidity from savings accounts in times of overdraft. Finally, I show that those mobile-banking adopters, who formerly did not use the online banking service of the bank, benefit from mobile-banking adoption the strongest.