The increasing prevalence of smartphone technology has opened new avenues for health and fitness monitoring, particularly through portable systems designed for exercise tracking and repetition counting. This paper designs, develops, and evaluates a camera-based portable exercise monitoring system realized on an ESP32-CAM module integrated with a smartphone. Advanced pose estimation algorithms in the system automatically detect and count the repetition in push-ups, sit-ups, and squat jumps. It captures real-time data to raise user engagement and accuracy with immediate feedback in an exercise routine without intrusive wearable devices. The portable nature of this solution makes it accessible for a wide range of users, particularly in personal fitness and rehabilitation contexts. Such a portable solution provides practical and accessible tools to apply in the areas of personal fitness monitoring and rehabilitation, so that adherence to exercise regimens is improved in order to improve health outcomes. Therefore, future work will be invested toward optimization of algorithms within the system and extending its abilities to a set of exercises or different user environments.