This European Technical Specification will provide a set of requirements for developers of health and wellness apps, intending to meet the needs of health care professionals, patients, carers and the wider public. It will include a set of quality criteria and cover the app project life cycle, through the development, testing, releasing and updating of an app, including native, hybrid and web based apps, those apps associated with wearable, ambient and other health equipment and apps that are linked to other apps. It will also address fitness for purpose and the monitoring of usage. The specification will inform the development of health and wellness apps irrespective of whether they are placed in the market, and including free of charge. The specification will not cover the processes or criteria that an app developer or publisher follow to establish whether a health and wellness app is subject to regulatory control (e.g. as a medical device, or related to information governance).