What thing the mobile information apparatus of the next generation become? The demand of the user to mobile information apparatus was regarded as a key which knows that. So, questionnaires were carried out and the user demands about "carrying", "function", "communication", "operation" and "contents" were investigated. The result, it became clear that a card type, a function-customization type, etc are demands of users. And, the following three points were proposed as a concept of the next generation mobile information apparatus. (1)Customization of the function by the combination of a part. (2)Realization of communication existence of a partner is in sight. (3)Realization of the system which can obtain surrounding environment information.