This study aimed at showing that the classes of generalized non-expansive mappings due to Hardy and Rogers and the mappings satisfying Suzuki's condition (C) are independent and study some basic properties of generalized non-expansive mappings. Also, we introduce a new iterative scheme, called JF iterative scheme, and prove convergence results for generalized non-expansive mappings due to Hardy and Rogers in uniformly convex Banach spaces. Moreover, we show numerically that JF iterative scheme converges to a fixed point of generalized non-expansive mappings faster than some known and leading iterative schemes. As an application, we utilize newly defined iterative scheme to approximate the solution of a delay differential equation. Also, we present some nontrivial illustrative numerical examples to support main results. Our results are new and extend several relevant results in the existing literature.