Older adults are not reaching the recommended guidelines for physical activity. There is growing evidence that physical activity and positive emotions reinforce each other. However, the development of interventions leveraging this knowledge faces several challenges, such as the limited knowledge on the assessment of emotional wellbeing in daily life using technology. In this study, we investigate the experience of older adults regarding the use of mobile technology to coach physical activity and monitor emotional wellbeing during one month. Our results show that the participants became more aware of their daily physical activity and perceived an added value in using the technology in daily life. However, only limited added-value was perceived on monitoring positive emotions in daily life in the way we performed it. The most common argument concerned repetitiveness of the questions being asked every day. Moreover, participants also reported that they were not used to think about their emotions, what affected the way they answered the questions regarding their emotional wellbeing. Our results suggest that, to ensure reliability of the data, it is extremely important to hear the experience of the participants after performing studies in daily life.