Portable electronic devices such as smart phones and virtual-reality headsets provide clinicians with a powerful tool for improving evidence-based psychological treatments (see Nature 511, 287–289; 2014). For example, they offer patients more-frequent access to therapy and are likely to boost compliance.

Internet-based cognitive behavioural therapy, for instance, is effective for conditions such as depression and anxiety. Immersive virtual reality helps for some phobias, including fear of flying and fear of heights, and holds promise for conditions such as eating disorders and post-traumatic stress disorder (see G. Riva CyberPsychol. Behav. 8, 220–230; 2005).

Smartphones, in conjunction with wearable sensors, convey information about patients' activity, location and even physiological responses, providing insight into how well they function in everyday life and guiding decisions on mental-health interventions.

Virtual reality could also be a useful tool for researchers investigating the neural basis of functional and dysfunctional psychological processes (see C. J. Bohil et al. Nature Rev. Neurosci. 12, 752–762; 2011).