Getting Interest on Holdings and Deposits. Also, certain applications provide users the option to earn interest on cash deposits or cryptocurrency holdings, giving them a long-term, passive cash withdrawal appopportunity to increase their savings. Finally, those who want to generate extra income or accumulate long-term wealth have a range of options with money-making applications. There are numerous ways to use smartphone apps to improve your financial situation, including taking surveys, shopping online, selling goods, investing in the stock market, and generating passive income.