An Exploratory Study to Evaluate a Digital Intervention to Disrupt Scratching in Atopic Dermatitis and Psoriasis

Inclusion Criteria: * Fluent in written and spoken English, confirmed by ability to read, understand and sign the informed consent form (ICF). * Lives in the United States. * Aged 18 years or older. * Itch NRS ≥ 4 during screening. * Meets indication-specific inclusion criteria (see Appendix 1), as reported by the study participant with adequate clinical documentation. (Documentation to be provided to the study team upon request.) * Has an active email address and is willing and able to receive and respond to email messages. * Has access to an internet connection during the study duration. * Willing and able to comply with the study protocol and assessments. * Is the sole user of an iPhone with an iPhone operating system (OS) 14 or later or a smartphone with an Android OS 10 or later for the duration of the study. * Is willing and able to receive Short Message Service (SMS) text messages and notifications on their smartphone. Exclusion Criteria: * Pregnant or planning to become pregnant. * Visual, dexterity or cognitive deficit so severe that it precludes the use of an App-based, reaction-time-based activity per investigator judgment. * Severe psychiatric disorder involving a history of psychosis (e.g., schizophrenia, bipolar disorder or severe personality disorders). * Psychiatric hospitalization in the past 6 months. * Participation in any research study (including studies on psychotherapy, mindfulness, cognitive training or pharmacological treatment) during the past 3 months. * Initiation or change in primary-disease-specific medication within 30 days prior to entering the study. * Self-reported substance-use disorder within the past 1 year. * Currently experiencing a skin infection. * Planning the introduction of new therapies (including studies on psychotherapy, mindfulness, cognitive training or pharmacological treatment) during the 7-week study period. * Anticipating a change in current pharmacological or psychotherapy treatment regimen during the 7-week study period.