Prehabilitation refers to the process of improving a patient's functional capabilities prior to a surgical procedure with the goal of decreasing post-surgical inactivity and physical decline. This clinical trial evaluates the utility of a personalized home-based prehabilitation exercise intervention for the improvement of physical function and surgical outcomes in patients with urothelial carcinoma undergoing definitive or consolidative surgery of the bladder (radical cystectomy) or upper tract (nephroureterectomy, ureterectomy) with or without preceding neoadjuvant/systemic therapy. The exercise intervention includes at-home exercise sessions focused on the improvement of core strength and balance as well as personalized step count goals, delivered to patients remotely via a smart-device-based application (ExerciseRx). Encouraging physical activity before surgery may improve physical function and surgical outcomes in patients who are scheduled to undergo surgery for their bladder or urothelial cancer.