This paper describes CAREUP, a novel older adult healthy aging support platform based on Intrinsic Capacity (IC) monitoring. Besides standard functionalities like storing health measurement data or providing users with personalized recommendations, the platform includes novel intrinsic capacity assessment and prediction algorithms. Older adults' performance is continuously monitored in all five IC domains-locomotion, psychology, cognition, vitality, and sensory capacity-based on measurement results and answers to questionnaires gathered using the platform's mobile applications. The users are also presented with a machine learning-based prediction of how their intrinsic capacity might change over the following years. The platform's operation was successfully tested with the participation of older adults and their caregivers in three countries: Austria, Italy, and Romania.