Mental fitness is as important as physical health for preventing conditions like depression and maintaining independence. E-mental health uses technology like computerized interventions, telehealth, wearable devices, social media, and gaming to deliver mental health services and information. These tools have benefits like increasing access to care, empowering patients, and incorporating real-time data monitoring. Realizing e-mental health's potential will require investment but it could transform care systems by tailoring services to individuals and giving patients more control over their health information and treatment.