Digital transformation drives all-round changes in production methods, business processes and management structures in the power industry. Digital technology is a key force in serving the development of the energy industry and building new power systems. With the continuous development of substation digital technology and the stabilization of the digital platform, the demand for application development around equipment and businesses in substations is increasing and becoming more and more urgent. A business-oriented, scenario-based, simple, and efficient customized application development platform is particularly important. This article introduces and researches the background, value, architecture, key technologies, application scenario examples, etc. of customized application development technology. Research and explore new models of application development, accumulate reusable service components, accelerate the speed of customized application development, reduce the complexity of application development, and improve application development efficiency.