Due to the exponential growth of the internet, smartphones, and communication technologies during the last two decades, the digital banking sector has enormously advanced in terms of user-friendly, efficient, and fast financial transactions. Digital banking also plays a significant role as an enabler of cashless transactions in the economic crisis caused by the COVID-19 pandemic. The study investigates the challenges, technology, and future research agenda of digital banking. The paper follows the manifestation of Kitchenham's SLR protocol. Six databases were used to determine articles that match the criteria. The study considers recent articles, which have been published from 2015 to 2021. Sixty-seven papers have been selected, extracted, and analyzed. The result highlights issues related to technology, organization, people, process, environment, customers, security, and risk, which become challenges in digital banking innovation. This research presents suggestions for future research directions, which will be beneficial to practitioners and scholars around the globe.