Fitbit trackers can be useful for seniors for several reasons. Firstly, they can help seniors track their physical activity levels and encourage them to stay active, which is important for maintaining overall health and preventing chronic conditions such as heart disease and diabetes. Additionally, Fitbit trackers can monitor sleep patterns and provide insights into sleep quality, which is important for seniors who may experience sleep disturbances. Some Fitbit models also have features such as reminders to move and guided breathing exercises that can help seniors stay active and reduce stress levels.