Foundation models for mobile devices are advancing toward greater diversity, intelligence, and generalization, gaining increasing academic and industrial attention. Their deployment across smartphones, tablets, laptops, and robots is transforming products and industries. Developing mobile-specific foundation models is crucial to address limited resources, network variability, and energy constraints, enabling efficient, private, and real-time on-device intelligence. This Recommendation specifies the requirements for the capabilities of mobile device foundation models, which will enable users to better understand the capabilities of mobile device foundation models in the process of deploying them in real-world applications. This Recommendation provides guidelines for users to examine the level of mobile device foundation models' capabilities and promote the effectiveness of applications.