With the support of national policy, agriculture has been integrated with rapidly developing information technology. New technologies such as the Internet of Things, artificial intelligence, cloud computing, and big data have been widely used in the field of agricultural production. After nearly a decade of development, various agricultural informatization application platforms have been formed that focus on Internet-of-Things-based agricultural monitoring supplemented by intelligent analysis. The demonstration of these platforms has promoted the modernization and transformation of traditional agriculture; however, the functional requirements of these platforms still need to be further integrated and improved to facilitate intelligent monitoring and sophisticated management in the overall agricultural production process. To improve the overall level of informatization of field crop production, this paper presents a comprehensive service platform for intelligent crop production in the field using a wide range of information technologies such as the agricultural Internet of Things, intelligent control, decision-making models, and big data mining. It integrates eight major business processes, including Internet-of-Things-based environmental perception, nitrogen fertilizer decision-making, agricultural remote sensing services, the intelligent management of water and nitrogen, pest monitoring and early warning, product traceability, and agricultural technology promotion, and provides a big data platform. The demonstration of the platform shows that its information services are rich in content, which meets the needs of different users for agricultural production-related data services and improves the precise management of the field crop production process. The proposed platform substantially advances the baseline for a comprehensive application for modern information technology in the intelligent production of field crops.